, each in his respective apology, imply that it was his own questioning mind and what was perceived as the bad moral influence he had on his young men that led to his trial and condemnation. socrates left no philosophical works, and apparently wrote none. his philosophy and personality were made known to later generations through the dialogues that several of his associates wrote with him as principal speaker ( see socratic dialogues ). only fragments survive of those by aeschines of sphettus and antisthenes, both athenians, and phaedo of elis ( after whom plato ' s dialogue phaedo is named ). our own knowledge of socrates depends primarily on the dialogues of plato and the socratic works of the military leader and historian xenophon. plato was a young associate of socrates ' during perhaps the last ten years of his life, and xenophon knew him during that same period, though he was absent from athens at the time of socrates ' death and for several years before and many years after. we also have secondary evidence from the comic playwright aristophanes and from aristotle. aristotle, although born fifteen years after socrates ' death, had access through plato and others to first - hand information about the man and his philosophy. aristophanes knew socrates personally ; his clouds ( first produced c. 423 bc ) pillories the ' new ' education offered by sophists and philosophers by showing socrates at work in a ' thinkery ', propounding outlandish physical theories and teaching young men how to argue cleverly in defence of their improper behaviour. it is significant that in 423, when socrates was about 45 years old, he could plausibly be taken as a leading representative in athens of the ' new ' education. but one cannot expect a comic play making fun of a whole intellectual movement to contain an authentic account of socrates ' specific philosophical commitments. however, the literary genre to which plato ' s and xenophon ' s socratic works belong ( along with the other, lost dialogues ) also permits the author much latitude ; in his poetics aristotle counts such works as fictions of a certain kind, alongside epic poems and tragedies. they are by no means records of actual discussions ( despite the fact that xenophon explicitly so represents his ). each author was free to develop his own ideas behind the mask of socrates, at least within the limits of what his personal experience had led him to believe was socrates ' basic philosophical and moral outlook. especially in view of the many inconsistencies


. each author was free to develop his own ideas behind the mask of socrates, at least within the limits of what his personal experience had led him to believe was socrates ' basic philosophical and moral outlook. especially in view of the many inconsistencies between plato ' s and xenophon ' s portraits ( see § 7 below ), it is a difficult question for historical - philosophical interpretation whether the philosophical and moral views the character socrates puts forward in any of these dialogues can legitimately be attributed to the historical philosopher. the problem of interpretation is made more difficult by the fact that socrates appears in many of plato ' s dialogues - ones belonging to his middle and later periods ( see plato § § 10 - 16 ) - discussing and expounding views that we have good reason to believe resulted from plato ' s own philosophical investigations into questions of metaphysics and epistemology, questions that were not entered into at all by the historical socrates. to resolve this problem - what scholars call the ' socratic problem ' - most agree in preferring plato to xenophon as a witness. xenophon is not thought to have been philosopher enough to have understood socrates well or to have captured the depth of his views and his personality. as for plato, most scholars accept only the philosophical interests and procedures, and the moral and philosophical views, of the socrates of the early dialogues, and, more guardedly, the socrates of ' transitional ' ones such as meno and gorgias, as legitimate representations of the historical personage. these dialogues are the ones that predate the emergence of the metaphysical and epistemological inquiries just referred to. however, even plato ' s early dialogues are philosophical works written to further plato ' s own philosophical interests. that could produce distortions, also ; and xenophon ' s relative philosophical innocence could make his portrait in some respects more reliable. moreover, it is possible, even probable, that in his efforts to help his young men improve themselves socrates spoke differently to the philosophically more promising ones among them - including plato - from the way he spoke to others, for example xenophon. both portraits could be true, but partial and needing to be combined ( see § 7 ). the account of socrates ' philosophy given below follows plato, with caution, while giving independent weight also to xenophon and to aristotle. xenophon ' s apology of socrates, symposium and memorabilia ( or memoirs ) may well reflect knowledge of plato ' s own apology and some of his early and middle period dialogues, as well as lost


weight also to xenophon and to aristotle. xenophon ' s apology of socrates, symposium and memorabilia ( or memoirs ) may well reflect knowledge of plato ' s own apology and some of his early and middle period dialogues, as well as lost dialogues of antisthenes and others. xenophon composed the memorabilia over many years, beginning only some ten years after socrates ' death, avowedly in order to defend socrates ' reputation as a good man, a true athenian gentleman, and a good influence upon his young men. the same intention motivated hisapology and symposium. anything these works contain about socrates ' philosophical opinions and procedures is ancillary to that apologetic purpose. plato ' s apology, of course, is similarly apologetic, but it and his other early dialogues are carefully constructed discussions, strongly focused upon questions of philosophical substance. plato evidently thought socrates ' philosophical ideas and methods were central to his life and to his mission. xenophon ' s and plato ' s testimony are agreed that socrates ' discussions consistently concerned the aretai, the recognized ' virtues ' or excellences of character ( see aret ), such as justice, piety, self - control or moderation ( sophrosyn ), courage and wisdom ; what these individual characteristics consist in and require of a person, what their value is, and how they are acquired, whether by teaching or in some other way. in his apology and elsewhere plato has socrates insist that these discussions were always inquiries, efforts made to engage his fellow - discussants in coming jointly to an adequate understanding of the matters inquired into. he does not himself know, and therefore cannot teach anyone else - whether by means of these discussions or in some other way - either how to be virtuous or what virtue in general or any particular virtue is. furthermore, given his general characterization of virtue ( see § § 4 - 5 ), plato ' s socrates makes a point of suggesting the impossibility in principle of teaching virtue at all, by contrast with the sophists who declared they could teach it. virtue was not a matter of information about living or rote techniques of some sort to be handed on from teacher to pupil, but required an open - ended personal understanding that individuals could only come to for themselves. xenophon, too, reports that socrates denied he was a teacher of aret, but he pays no attention to such issues of philosophical principle. he does not hesitate to show socrates speaking of himself as a teacher ( see apology 26, memorabilia i 6. 13 -


too, reports that socrates denied he was a teacher of aret, but he pays no attention to such issues of philosophical principle. he does not hesitate to show socrates speaking of himself as a teacher ( see apology 26, memorabilia i 6. 13 - 14 ), and describes him as accepting young men from their fathers as his pupils ( but not for a fee ), and teaching them the virtues by displaying his own virtues to them for emulation, as well as through conversation and precepts. perhaps socrates did not insist on holding to strict philosophical principles in dealing with people on whom their point would have been lost. in his apology plato ' s socrates traces his practice of spending his days discussing and inquiring about virtue to an oracle delivered at the shrine of apollo at delphi. xenophon also mentions this oracle in his apology. a friend of socrates ', chaerephon, had asked the god whether anyone was wiser than socrates ; the priestess answered that no one was. because he was sure he was not wise at all - only the gods, he suspected, could actually know how a human life ought to be led - socrates cross - examined others at athens with reputations for that kind of wisdom. he wanted to show that there were people wiser than he and thus discover the true meaning of the oracle - apollo was known to speak in riddles requiring interpretation to reach their deeper meaning. in the event, it turned out that the people he examined were not wise, since they could not even give a self - consistent set of answers to his questions : obviously, true knowledge requires at least that one think and speak consistently on the subjects one professes to know. so he concluded that the priestess ' s reply had meant that of all those with reputations for wisdom only he came close to deserving it ; he wisely did not profess to know these things that only gods can know, and that was wisdom enough for a human being. because only he knew that he did not know, only he was ready earnestly to inquire into virtue and the other ingredients of the human good, in an effort to learn. he understood therefore that apollo ' s true intention in the oracle had been to encourage him to continue his inquiries, to help others to realize that it is beyond human powers actually to know how to live - that is the prerogative of the gods - and to do his best to understand as far as a human being can how one ought to live. the life of philosophy, as led by him, was


human powers actually to know how to live - that is the prerogative of the gods - and to do his best to understand as far as a human being can how one ought to live. the life of philosophy, as led by him, was therefore something he was effectively ordered by apollo to undertake. we must remember that socrates was on trial on a charge of ' impiety '. in tracing his philosophical vocation back to apollo ' s oracle, and linking it to a humble recognition of human weakness and divine perfection, he was constructing a powerful rebuttal of the charges brought against him. but it cannot be literally true - if that is what he intended to say - that socrates began his inquiries about virtue only after hearing of the oracle. chaerephon ' s question to apollo shows he had established a reputation in athens for wisdom before that. that reputation cannot have rested on philosophical inquiries of another sort. in plato ' s phaedo socrates says he had been interested as a young man in philosophical speculations about the structure and causes of the natural world, but he plainly did not take those interests very far ; and in any event, his reputation was not for that kind of wisdom, but wisdom about how to lead a human life. in fact we do not hear of the duty to apollo in xenophon, or in other dialogues of plato, where we might expect to find it if from the beginning socrates thought apollo had commanded his life of philosophizing. however, we need not think socrates was false to the essential spirit of philosophy as he practised it if in looking back on his life under threat of condemnation for impiety he chose, inaccurately, to see it as initially imposed on him by apollo ' s oracle. despite its impressiveness, socrates ' speech failed to convince his jury of 501 male fellow citizens, and he died in the state prison by drinking hemlock as required by law. his speech evidently offended the majority of the jurors by its disdain for the charges and the proceedings ; xenophon explains his lofty behaviour, which he thinks would otherwise have been lunatic - and damaging to his reputation - by reporting that he had told friends in advance that as a 70 - year - old still in possession of his health and faculties it was time for him to die anyhow, before senility set in. furthermore, his ' divine sign ' - the ' voice ' he sometimes heard warning him for his own good against a contemplated course of action - had prevented him from spending time crafting a defence speech


to die anyhow, before senility set in. furthermore, his ' divine sign ' - the ' voice ' he sometimes heard warning him for his own good against a contemplated course of action - had prevented him from spending time crafting a defence speech. ( this voice seems to have been the basis for the charge of introducing ' new ' gods. ) so he would do nothing to soften his manner in order to win his freedom. even if this story is true, plato could be right that socrates put on a spirited, deeply serious defence of his life and beliefs - one that he thought should have convinced the jurors of his innocence, if only they had judged him intelligently and fairly. in cross - examining those with reputations for wisdom about human affairs and showing their lack of it, socrates employed a special method of dialectical argument that he himself had perfected, the method of ' elenchus ' - greek for ' putting to the test ' or ' refutation '. he gives an example at his trial when he cross - examines meletus, one of his accusers ( plato, apology 24d - 27e ). the respondent states a thesis, as something he knows to be true because he is wise about the matter in question. socrates then asks questions, eliciting clarifications, qualifications and extensions of the thesis, and seeking further opinions of the respondent on related matters. he then argues, and the respondent sees no way not to grant, that the original thesis is logically inconsistent with something affirmed in these further responses. for socrates, it follows at once that the respondent did not know what he was talking about in stating his original thesis : true knowledge would prevent one from such self - contradiction. so the respondent suffers a personal set - back ; he is refuted - revealed as incompetent. meletus, for example, does not have consistent ideas about the gods or what would show someone not to believe in them, and he does not have consistent ideas about who corrupts the young, and how ; so he does not know what he is talking about, and no one should take his word for it that socrates disbelieves in the gods or has corrupted his young men. in many of his early dialogues plato shows socrates using this method to examine the opinions of persons who claim to be wise in some matter : the religious expert euthyphro on piety ( euthyphro ), the generals laches and nicias on courage ( lac


dialogues plato shows socrates using this method to examine the opinions of persons who claim to be wise in some matter : the religious expert euthyphro on piety ( euthyphro ), the generals laches and nicias on courage ( laches ), the sophist protagoras on the distinctions among the virtues and whether virtue can be taught ( protagoras ), the rhapsodist ion on what is involved in knowing poetry ( ion ), the budding politician alcibiades on justice and other political values ( alcibiades ), the sophist hippias on which was the better man, odysseus or achilles ( lesser hippias ), and on the nature of moral and aesthetic beauty ( greater hippias ). they are all refuted - shown to have mutually inconsistent ideas on the subject discussed ( see plato § § 4, 6, 8 - 9 ). but socrates is not content merely to demonstrate his interlocutor ' s lack of wisdom or knowledge. that might humiliate him into inquiring further or seeking by some other means the knowledge he has been shown to lack, instead of remaining puffed up with self - conceit. that would be a good thing. but socrates often also indicates clearly that his cross - examination justifies him and the interlocutor in rejecting as false the interlocutor ' s original thesis. logically, that is obviously wrong : if the interlocutor contradicts himself, at least one of the things he has said must be false ( indeed, all of them could be ), but the fact alone of self - contradiction does not show where the falsehood resides. for example, when socrates leads euthyphro to accept ideas that contradict his own definition of the pious as whatever pleases all the gods, socrates concludes that that definition has been shown to be false ( euthyphro 10d - 11a ), and asks euthyphro to come up with another one. he does not usually seem to consider that perhaps on further thought the additional ideas would seem faulty and so merit rejection instead. socrates uses his elenctic method also in discussion with persons who are not puffed up with false pride, and are quite willing to admit their ignorance and to reason out the truth about these important matters. examples are his discussions with his long - time friend crito on whether he should escape prison and set aside the court ' s death sentence ( plato,


, and are quite willing to admit their ignorance and to reason out the truth about these important matters. examples are his discussions with his long - time friend crito on whether he should escape prison and set aside the court ' s death sentence ( plato, crito ), and with the young men charmides, on self - control ( charmides ), and lysis and menexenus, on the nature of friendship ( lysis ). socrates examines crito ' s proposal that he escape on the basis of principles that he presents to him for his approval, and he, together with crito ( however half - heartedly ), rejects it when it fails to be consistent with them. and he examines the young men ' s successive ideas about these virtues, rejecting some of them and refining others, by relying on their own acceptance of further ideas that he puts to them. again, he is confident that the inconsistencies brought to light in their ideas indicate the inadequacy of their successive proposals as to the nature of the moral virtue in question. in many of his discussions, both with young men and the allegedly wise, socrates seeks to know what some morally valuable property is - for example, piety, courage, self - control or friendship ( see § 5 ). rejecting the idea that one could learn this simply from attending to examples, he insisted on an articulated ' definition ' of the item in question - some single account that would capture all at once the presumed common feature that would entitle anything to count as a legitimate instance. such a definition, providing the essence of the thing defined, would give us a ' model ' or ' paradigm ' to use in judging whether or not some proposed action or person possesses the moral value so defined ( euthyphro 6d - e ). aristotle says ( in metaphysics i, 6 ) that socrates was the first to interest himself in such ' universal definitions ', and traces to his interest in them plato ' s first impetus towards a theory of forms, or ' separated ' universals ( see plato § 10 ). in none of his discussions in plato ' s early works does socrates profess to think an adequate final result has actually been established - about the nature of friendship, or self - control, or piety, or any of the other matters he inquires about. indeed, on the contrary, these works regularly end with professions of profound ignorance about the matter under investigation. knowledge is never attained, and further questions always remain to be considered. but socrates


, or any of the other matters he inquires about. indeed, on the contrary, these works regularly end with professions of profound ignorance about the matter under investigation. knowledge is never attained, and further questions always remain to be considered. but socrates does plainly think that progress towards reaching final understanding has taken place ( even if only a god, and no human being, could ever actually attain it ). not only has one discovered some things that are definitely wrong to say ; one has also achieved some positive insights that are worth holding onto in seeking further systematic understanding. given that socrates ' method of discussion is elenctic throughout, what does he think justifies this optimism? on balance, our evidence suggests that socrates had worked out no elaborate theory to support him here. the ideas he was stimulated to propound in an elenctic examination which went against some initial thesis seemed to him, and usually also to the others present, so plausible, and so supportable by further considerations, that he and they felt content to reject the initial thesis. until someone came up with arguments to neutralize their force, it seemed the thesis was doomed, as contrary to reason itself. occasionally socrates expresses himself in just those terms : however unpalatable the option might seem, it remains open to someone to challenge the grounds on which his conclusions rest ( see euthyphro 15c, gorgias 461d - 462a, 509a, crito 54d ). but until they do, he is satisfied to treat his and his interlocutor ' s agreement as a firm basis for thought and action. later, when plato himself became interested in questions of philosophical methodology in his meno, this came to seem a philosophically unsatisfactory position ; plato ' s demand for justification for one ' s beliefs independent of what seemed on reflection most plausible led him to epistemological and metaphysical inquiries that went well beyond the self - imposed restriction of socratic philosophy to ethical thought in the broadest sense. but socrates did not raise these questions. in this respect more bound by traditional views than plato, he had great implicit confidence in his and his interlocutors ' capacity, after disciplined dialectical examination of the issues, to reach firm ground for constructing positive ideas about the virtues and about how best to lead a human life - even if these ideas never received the sort of final validation that a god, understanding fully the truth about human life, could give them. the topics socrates discussed were always ethical, and never included questions of physical


about how best to lead a human life - even if these ideas never received the sort of final validation that a god, understanding fully the truth about human life, could give them. the topics socrates discussed were always ethical, and never included questions of physical theory or metaphysics or other branches of philosophical study. moreover, he always conducted his discussions not as theoretical inquiries but as profoundly personal moral tests. questioner and interlocutor were equally putting their ways of life to what socrates thought was the most important test of all - their capacity to stand up to scrutiny in rational argument about how one ought to live. in speaking about human life, he wanted his respondents to indicate what they truly believed, and as questioner he was prepared to do the same, at least at crucial junctures. those beliefs were assumed to express not theoretical ideas, but the very ones on which they themselves were conducting their lives. in losing an argument with socrates you did not merely show yourself logically or argumentatively deficient, but also put into question the very basis on which you were living. your way of life might ultimately prove defensible, but if you cannot now defend it successfully, you are not leading it with any such justification. in that case, according to socrates ' views, your way of life is morally deficient. thus if menexenus, lysis and socrates profess to value friendship among the most important things in life and profess to be one another ' s friends, but cannot satisfactorily explain under pressure of elenctic investigation what a friend is, that casts serious doubt on the quality of any ' friendship ' they might form ( plato, lysis 212a, 223b ). moral consistency and personal integrity, and not mere delight in argument and logical thought, should therefore lead you to repeated elenctic examination of your views, in an effort to render them coherent and at the same time defensible on all sides through appeal to plausible arguments. or, if some of your views have been shown false, by conflicting with extremely plausible general principles, it behoves you to drop them - and so to cease living in a way that depends upon accepting them. in this way, philosophical inquiry via the elenchus is fundamentally a personal moral quest. it is a quest not just to understand adequately the basis on which one is actually living, and the personal and moral commitments that this contains. it is also a quest to change the way one lives as the results of argument show one ought to, so


it is a quest not just to understand adequately the basis on which one is actually living, and the personal and moral commitments that this contains. it is also a quest to change the way one lives as the results of argument show one ought to, so that, at the logical limit of inquiry, one ' s way of life would be completely vindicated. accordingly, socrates in plato ' s dialogues regularly insists on the individual and personal character of his discussions. he wants to hear the views of the one person with whom he is speaking. he dismisses as of no interest what outsiders or most people may think - provided that is not what his discussant is personally convinced is true. the views of ' the many ' may well not rest on thought or argument at all. socrates insists that his discussant shoulder the responsibility to explain and defend rationally the views he holds, and follow the argument - reason - wherever it may lead. we learn a good deal about socrates ' own principles from both plato and xenophon. those were ones that had stood up well over a lifetime of frequent elenctic discussions and had, as he thought, a wealth of plausible arguments in their favour. foremost is his conviction that the virtues - self - control, courage, justice, piety, wisdom and related qualities of mind and soul - are essential if anyone is to lead a good and happy life. they are good in themselves for a human being, and they guarantee a happy life, eudaimonia - something that he thought all human beings always wanted, and wanted more than anything else. the virtues belong to the soul - they are the condition of a soul that has been properly cared for and brought to its best state. the soul is vastly more important for happiness than are health and strength of the body or social and political power, wealth and other external circumstances of life ; the goods of the soul, and pre - eminently the virtues, are worth far more than any quantity of bodily or external goods. socrates seems to have thought these other goods are truly good, but they only do people good, and thereby contribute to their happiness, under the condition that they are chosen and used in accordance with virtues indwelling in their souls ( see plato, apology 30b, euthydemus 280d - 282d, meno 87d - 89a ). more specific principles followed. doing injustice is worse for oneself than being subjected to it ( gorgias 469c - 522e ) : by acting unjustly you make your soul worse


courageous, or wise? if you did not know that, you would not know what to do in order to acquire those qualities. furthermore, supposing you did possess a virtue, you would have to be able to explain and defend by argument the consequent ways in which you lived - otherwise your conviction that those are ways one ought to act would be shallow and unjustified. and in order to do that you would have to know what state of mind the virtue was, since that is essential to them ( see plato, charmides 158e - 159a ). consequently, in his discussions socrates constantly asked for ' definitions ' of various virtues : what is courage ( laches ) ; what is self - control or moderation ( charmides ), what is friendship ( lysis ) and what is piety ( euthyphro ). as this context shows, he was asking not for a ' dictionary definition ', an account of the accepted linguistic understanding of a term, but for an ethically defensible account of an actual condition of mind or character to which the word in common use would be correctly applied. in later terminology, he was seeking a ' real ' rather than a ' nominal ' definition ( see definition ; plato § § 6 - 9 ). socrates objected to definitions that make a virtue some external aspect of a virtuous action ( such as the manner in which it is done - for example its ' quiet ' or measured quality in the case of moderation, charmides 160b - d ), or simply the doing of specific types of action, described in terms of their external circumstances ( such as, for courage, standing one ' s ground in battle ; laches 190e - 191d ). he also objected to more psychological definitions that located a virtue in some non - rational and non - cognitive aspect of the soul ( for example, in the case of courage, the soul ' s endurance or strength of resistance ) ( laches 192d - 193e ). for his own part, he regularly shows himself ready to accept only definitions that identify a virtue with some sort of knowledge or wisdom about what is valuable for a human being. that ' intellectualist ' expectation about the nature of virtue, although never worked out to his satisfaction in any platonic dialogue, is central to socrates ' philosophy. given that in his discussions he is always the questioner, probing the opinions of his respondent and not arguing for views of his own, we never find socrates stating clearly what led him to this intellectualism


dialogue, is central to socrates ' philosophy. given that in his discussions he is always the questioner, probing the opinions of his respondent and not arguing for views of his own, we never find socrates stating clearly what led him to this intellectualism. probably, however, it was considerations drawn from the generally agreed premise that each virtue is a condition motivating certain voluntary actions, chosen because they are good and fine or noble. he took it that what lies behind and produces any voluntary action is the idea under which it is done, the conception of the action in the agent ' s mind that makes it seem the thing to do just then. if so, each virtue must be some state of the mind, the possessor of which constantly has certain distinctive general ideas about how one ought to behave. furthermore, since virtues get this right, these are true ideas. and since a virtuous person acts well and correctly in a perfectly reliable way, they must be seated so deeply in the mind as to be ineradicable and unwaveringly present. the only state of mind that meets these conditions is knowledge : to know a subject is not just to be thoroughly convinced, but to have a deep, fully articulated understanding, being ready with explanations to fend off objections and apparent difficulties and to extend old principles into new situations, and being prepared to show with the full weight of reason precisely why each thing falling under it is and must be so. each virtue, then, must be knowledge about how one ought to behave in some area of life, and why - a knowledge so deep and rationally secure that those who have it can be counted upon never to change their minds, never to be argued out of or otherwise persuaded away from, or to waver in, their conviction about how to act. in plato ' s protagoras socrates goes beyond this, and identifies himself with the position, rejected by protagoras in their discussion, that the apparently separate virtues of justice, piety, self - control, courage and wisdom are somehow one and the same thing - some single knowledge ( 361a - b ). xenophon too confirms that socrates held this view ( memorabilia iii 9. 5 ). protagoras defends the position that each of the virtues is not only a distinct thing from each of the others, but so different in kind that a person could possess one of them without possessing the others ( 329d - e ). in opposing him, socrates sometimes speaks plainly of two allegedly distinct virtues being


is not only a distinct thing from each of the others, but so different in kind that a person could possess one of them without possessing the others ( 329d - e ). in opposing him, socrates sometimes speaks plainly of two allegedly distinct virtues being ' one ' ( 333b ). given this unity of the virtues, it would follow that a person could not possess one without having them all. and in speaking of justice and piety in particular, socrates seems to go further, to imply that every action produced by virtue is equally an instance of all the standardly recognized virtues : pious as well as just, wise and self - controlled and courageous also. among his early dialogues, however, plato ' s own philosophical interests show themselves particularly heavily in the protagoras, so it is doubtful how far the details of his arguments are to be attributed to the historical socrates. the issues raised by socrates in the protagoras were, none the less, vigorously pursued by subsequent ' socratic ' philosophers ( as plutarch ' s report in on moral virtue 2 demonstrates ). and the positions apparently adopted by plato ' s socrates were taken up and ingeniously defended by the stoic philosopher chrysippus ( see stoicism § 16 ). as usual, because of his questioner ' s role, it is difficult to work out socrates ' grounds for holding to the unity of virtue ; and it is difficult to tell whether, and if so how, he allowed that despite this unity there were some real differences between, say, justice and self - control, or courage and piety. apparently he thought the same body of knowledge - knowledge of the whole of what is and is not good for human beings, and why it is so or not - must at least underlie the allegedly separate virtues. if you did not have that vast, comprehensive knowledge you could not be in the state of mind which is justice or in that which is courage, and so on ; and if you did have it you would necessarily be in those states of mind. it seems doubtful whether socrates himself progressed beyond that point. efforts to do that were made by chrysippus and the other philosophers referred to above. and despite denying that all virtues consist in knowledge, plato in the republic and aristotle in nicomachean ethics vi follow socrates to the extent of holding, in different ways, that you need to have all the virtues in order to have any one. in plato ' s protagoras socrates also denies the possibility of weakness of will -


of alternative sources of motivation that produce voluntary action on their own ( see stoicism § 19 ). in fact, during hellenistic times it was the socratic, ' unitary ' psychology of action that carried the day ; the platonic - aristotelian alternative, dominant in the ' common sense ' and the philosophy of modern times, was a minority view. the issues socrates raised about weakness of will continue to be debated today. socrates drew to himself many of the brightest and most prominent people in athens, securing their fascinated attention and their passionate friendship and support. his effectiveness as a philosopher, and the socratic ' legend ' itself, depended as much on the strength and interest of his personality as on the power of his mind. plato ' s and xenophon ' s portraits of socrates as a person differ significantly, however. plato ' s socrates is aloof and often speaks ironically, although also with unusual and deeply held moral convictions ; paradoxically, the depth and clarity of his convictions, maintained alongside the firm disclaimer to know what was true, could seem all the stronger testimony to their truth, and made them felt the more strongly as a rebuke to the superficiality of one ' s own way of living. in xenophon, socrates is also sometimes ironical and playful, especially in the symposium, but his conversation is usually direct, even didactic, and often chummy in tone ; his attitudes are for the most part conventional though earnest ; and there is nothing to unsettle anyone or make them suspect hidden depths. it is much easier to believe that the socrates of plato ' s dialogues could have had such profound effects on the lives of the brightest of his contemporaries than did the character in xenophon. that is one reason given for trusting plato ' s more than xenophon ' s portrait of the historical personage. but perhaps socrates used the more kindly and genial manner and conventional approach depicted by xenophon to draw out the best in some of his young men and his friends - ones who would have been put off by the platonic subtleties. the historical socrates may have been a more complex person than even plato presents. plato and xenophon both represent socrates as strongly attracted to good - looking young men in the ' bloom ' of their middle to late teens, just the period when they were also coming of age morally and intellectually. in both he speaks of himself as unusually ' erotic ' by temperament and constantly ' in love '. but he explains his ' erotic ' attachments in terms


to late teens, just the period when they were also coming of age morally and intellectually. in both he speaks of himself as unusually ' erotic ' by temperament and constantly ' in love '. but he explains his ' erotic ' attachments in terms of his desire to converse with bright and serious young men, to question them about virtue and how best to live a human life, and to draw out what was best in their minds and characters. in xenophon he describes his love as love for their souls, not their bodies, and he vigorously condemns sexual relations with any young man : using him that way disgraces him and harms him by encouraging a loose attitude as regards physical pleasures symposium 8 ). the overheated sexuality of plato ' s own accounts ( symposium and phaedrus ) of eros, sexual love, for a young man ' s beauty as motivating an adult male to pursue philosophical truth into an eternal realm of forms ( see plato § 12 ) is to be distinguished sharply from socrates ' ideas, as we can gather them from xenophon and from plato ' s own early dialogues. xenophon emphasizes socrates ' freedom from the strong appetites for food, drink, sex and physical comfort that dominate other people ; his enkrateia or self - mastery is the first of the virtues that xenophon claims for him ( memorabilia i 2. 1 ). he was notorious for going barefoot even in winter and dressing always in a simple cloak. socrates ' self - mastery was at the centre of antisthenes ' portrayal, and is reflected also in several incidents reported in plato, such as his serene dismissal of the young alcibiades ' efforts to seduce him sexually ( plato, symposium 217b - 219e ), or, perhaps when engrossed in a philosophical problem, his standing in the open ( during a break in the action while on military service ) from morning to night, totally indifferent to everything around him ( symposium 220c - d ). this ' ascetic ' socrates, especially as presented by antisthenes - rejecting conventional comforts and conventional behaviour - became an inspiration for the ' cynics ' of later centuries ( see cynics ). looking back on the early history of philosophy, later philosophers traced to socrates a major turn in its development. as cicero puts it : ' socrates was the first to call philosophy down from the heavens... and compel it to ask questions about life and morality ' ( tusculan disputations v


to socrates a major turn in its development. as cicero puts it : ' socrates was the first to call philosophy down from the heavens... and compel it to ask questions about life and morality ' ( tusculan disputations v 10 - 11 ). previously it had been concerned with the origins and nature of the physical world and the explanation of celestial and other natural phenomena. modern scholarship follows the ancients ' lead in referring standardly to philosophers before socrates collectively as ' presocratics ' ( see presocratic philosophy ). this includes democritus, in fact a slightly younger contemporary of socrates ; cicero ' s verdict needs adjustment, in that democritus, independently of socrates, also investigated questions about ethics and morality. with the sole exception of epicureanism, which developed separately out of democritean origins, all the major movements of greek philosophy after socrates had roots in his teaching and example. this obviously applies to plato, whose philosophical development began with a thorough reworking and assimilation of socratic moral inquiry, and through him to aristotle and his fellow members of plato ' s academy, speusippus and xenocrates and others, as well as to later platonists. among socrates ' inner circle were also aristippus of cyrene, who founded the hedonist cyrenaic school ( see aristippus the elder ; cyrenaics ), and antisthenes, an older rival of plato ' s and major teacher in athens of philosophical dialectic. both of these figure in xenophon ' s memorabilia ( antisthenes also in his symposium ), where they are vividly characterized in conversation with socrates. another socratic, euclides, founded the megarian school ( see megarian school ). these ' socratic schools ' developed different themes already prominent in socrates ' own investigations, and competed in the claim to be his true philosophical heirs ( see socratic schools ; dialectical school ). in the third to first centuries bc, both the stoics and their rivals the academic sceptics claimed to be carrying forward the socratic tradition. in both cases this was based upon a reading of plato ' s dialogues and perhaps other eye - witness reconstructions of socrates ' philosophy. the academic arcesilaus interpreted the platonic socrates as a sceptical inquirer, avidly searching but never satisfied that the truth on any disputed question had been finally uncovered. he could point to much about plato ' s


' philosophy. the academic arcesilaus interpreted the platonic socrates as a sceptical inquirer, avidly searching but never satisfied that the truth on any disputed question had been finally uncovered. he could point to much about plato ' s socrates in support : his modest but firm denial that he possessed any knowledge, and his constant practice of inquiring into the truth by examining others ' opinions on the basis of ideas which they themselves accepted, without formally committing himself to these ideas even when he was the one to first suggest them. arcesilaus, however, applied his sceptical socratic dialectic to more than the questions of ethics and human life about which socrates himself had argued, making it cover the whole range of philosophical topics being investigated in his day. the stoics read the dialogues ( especially the euthydemus and protagoras ) quite differently. they found socrates espousing a complete doctrine of ethics and the psychology of human action. he posed his questions on the basis of this doctrine, leaving the respondent ( and the reader ) to recover for themselves the philosophical considerations underlying it. they thus emphasized the conceptions of virtue as knowledge, of virtue as unified in wisdom, and of voluntary action as motivated always by an agent ' s beliefs about what is best to do, that emerged through socrates ' examination of protagoras ( see § § 6 - 7 ). they thought these constituted a positive, socratic moral philosophy, and in their own moral theory they set out to revive and strengthen it with systematic arguments and with added metaphysical and physical speculations of their own. later stoics regularly referred to socrates as a genuine wise man or ' sage ', perhaps the only one who ever lived. he had brought to final, systematic perfection his knowledge, along stoic lines, of what is good and bad for human beings, and what is not, and therefore possessed all the virtues and no vices, and lived unwaveringly the best, happy life, free from emotion and all other errors about human life. it is a tribute to the complexity and enigmatic character of socrates that he could stand simultaneously as a paragon both of sceptical, non - committal inquiry and life led on that uncommitted basis, and of dogmatic knowledge of the final truth about all things human. the figure of socrates has continued to fascinate and to inspire ever - new interpretations of his innermost meaning. for montaigne, he proved that human beings can convincingly


and of dogmatic knowledge of the final truth about all things human. the figure of socrates has continued to fascinate and to inspire ever - new interpretations of his innermost meaning. for montaigne, he proved that human beings can convincingly and attractively order their own lives from their own resources of mind, without direction from god or religion or tradition. in the nineteenth century kierkegaard and nietzsche offered extensive interpretations of him, both heavily dependent upon hegel ' s absolute - idealist analysis. hegel interpreted socrates as a quintessentially negative thinker, aiming at making people vacillate in their superficial moral beliefs and endorse none of them wholeheartedly, thus hinting that the truth, although universal and objective, lies deep within the freedom of their own subjectivity. for kierkegaard he represents, on the contrary, the possibility of living wholeheartedly by occupying an unarticulated position somehow beyond the negative rejection but expressed through it : ' infinite absolute negativity '. in die geburt der tragodie ( the birth of tragedy ) nietzsche treats socrates principally as having poisoned the ' tragic ' attitude that made possible the great achievements of classical culture, by insisting that life should be grounded in rational understanding and justified by ' knowledge ' ; but his fascinated regard for socrates led him to return to him repeatedly in his writings. socrates was paradigmatically a philosopher whose thought, however taken up with logic and abstract argument, is inseparable from the search for self - understanding and from a deeply felt attachment to the concerns of human life. his power to fascinate and inspire is surely not exhausted. john m. cooper


today ’ s topic was chosen by gautum u, who attends caltech. he specifically asked for a “ serious blog post ” as opposed to a “ satire ” for this one. ( interestingly, the only other person who asked explicitly for a serious post was someone who chose the topic of free will for the 30th. it seems that philosophy is quite some serious business. ) what is the purpose of existence? it ’ s one of the most profound questions of metaphysics. it is even broader than the humanized form, what is the meaning of life? this specific one asks why we are here. but to be more general, we should ask, why is anything here? let us ask, why does earth exist? scientifically, there ’ s no real reason. take a look at the following : this image, known famously as the “ pale blue dot ” picture, was snapped by the voyager 1 spacecraft in 1991. that tiny pixel right there is earth, viewed from 4 billion miles away. indeed, from the scale of space, earth is just a speck of dust. galaxies, astronomers estimate, have 100 billion stars each. and there might be 100 billion galaxies in the visible universe. and according to the still debated multiverse theory, our universe may be only a tiny bubble in a vast sea of universes. and our earth is but one of the thousands of objects floating the sun. and humans have been on earth for only a tiny fraction of its history. it is like you are looking at an infinite beach, and you point at one grain of sand, and you ask, “ why does this grain of sand exist? ” it seems this is the wrong question. we should instead ask, “ why does this beach exist? ” why does the universe ( or multiverse ) exist? again, there doesn ’ t seem to be any intrinsic purpose. if you believe in god, you would say, the universe or multiverse exists because god created it. but then this turtles down to why does god exist? by most definitions of god, we would never be able to know. so generalizing the question does not seem like the right thing to do either, as it gets us nowhere. if it ’ s futile to ask why an atom exists, and also futile why the universe exists, then what is there to ask? why we exist. human beings. gautam ’ s topic as originally stated was “ the purpose of our existence ” ( emphasis added ). just like atoms to the entire universe, we don


martin harwit has argued that we cannot have made more than ten per cent of the crucial discoveries in astronomy. he uses what john barrow aptly calls ` the proof - readers argument '. if two independent readers look at a manuscript then it is possible to estimate, by comparing their different results, how many errors there must be in total, including those not identified. in an analogous way two independent astronomical channels ( say optical and x - ray ) can be used to examine the universe and a comparison of their separate key discoveries will yield an estimate of the numbers still to be found. in any case with so little data to work on it shouldn ' t be too difficult to devise a plausible theory to account for them. it is, however, sobering to compare the cosmological situation with the history of other sciences. take geology. men were living on the earth for millions of years, and quarrying rock, digging mines and canals and puzzling over its fossils for thousands of years, before unexpected palaeomagnetic patterns revealed for certain the key idea of continental drift. in stellar physics two thousand years elapsed between hipparcos ' s speculations and bessel ' s first measurement of a stellar distance. seventy years later the statistical patterns in the h - r diagram led to our understanding of stellar structure. however the closest comparison comes from my own field of galaxy astronomy which is, as an observational science, almost exactly contemporary with cosmology. although we now have good spectra and images of thousands of galaxies the list of fundamental things we don ' t know about them ( table 3 ) is far more striking that the list of things we do. | 1. | | how our knowledge is warped by selection effects. | | 2. | | what they are mostly made of. ( dark matter? ) | | 3. | | how they formed - and when. | | 4. | | how much internal extinction they suffer from. | | 5. | | what controls their global star - formation rates. | | 6. | | what parts their nuclei and halos play. | | 7. | | if there are genuine correlations among their global properties. | | 8. | | how they keep their gas / star balances. | of course these are only arguments by analogy. the optimistic cosmologist can always counter argue [ i don ' t know how ] that the universe in the large is a great deal simpler than its constituent parts.


| annu. rev. astron. astrophys. 1991. 29 : copyright © 1991 by. all rights reserved several major themes have emerged from the preceding discussion : | 1. | | in most or all galaxies, globular clusters are distinctly more metal - poor, by [ fe / h ] ~ - 0. 5, than the spheroid - population field stars. | | 2. | | both the average and range of cluster metallicity increase with galaxy size. these correlations parallel the ones for the metallicities of the galaxies themselves, and support the view that similar enrichment processes generated both types of halo subsystems. | | 3. | | globular clusters in all galaxies have similar, though not identical, luminosity distributions. for distance scale purposes, the calibrations of gclfs are not yet adequate for use as high - precision ( ± 0. 2 - mag ) standard candles. the present data are, however, sufficient to exert strong theoretical constraints favoring a universal cluster formation process insensitive to metallicity and with only modest later influences from dynamical evolution in most of the halo. | | 4. | | in giant ellipticals, gcss are often ( but not always ) more spatially extended than the halo light. a few have been shown to have higher velocity dispersions as well, and thus to form a dynamically different halo population than the spheroid stars. | | 5. | | in most large galaxies, the inner ~ 1 - 2 kpc of their spheroids have probably been almost totally depopulated of globular clusters through many dynamical mechanisms. at larger rgc, the effectiveness of these mechanisms falls off rapidly, leaving only gradual erosive processes. it is not yet clear if these processes act much differently in practice for disk galaxies as opposed to ellipticals. | | 6. | | in today ' s universe, few globular clusters are being formed ( that is, the formation of dense clusters with a characteristic mass ~ 105 - 6 m is extremely rare ). though there is no reason to believe that the processes of star cluster formation 15 gy ago were fundamentally different than today, the prevailing physical conditions of the protocluster gas then clearly favored more massive objects. the formation of globular clusters was an early, but secondary, process ( that is, clearly associated with their surrounding protogalaxies ). | | 7. | | arguments based on gcs spatial distributions, metallicity


more massive objects. the formation of globular clusters was an early, but secondary, process ( that is, clearly associated with their surrounding protogalaxies ). | | 7. | | arguments based on gcs spatial distributions, metallicity distributions, and dynamics suggest that the high - sn giant ellipticals such as in virgo and fornax did not form by mergers of disk galaxies or dwarfs. the merger scenario is, however, more viable for e galaxies in sparse environments ( smaller groups and the field ) and perhaps for some cd galaxies. | how else may we use gcss to understand the formation of galaxies? on the observational side, we need to fill in the many areas that are presently sketched out only with broad brush strokes : | 1. | | the metallicity distribution of gcs has proven to be an effective touchstone of interpretive models. we need to accumulate spectra of clusters in a wider variety of galaxies, combined with multicolor photometry in metallicity - sensitive indices. | | 2. | | luminosity function work has just begun to be exploited. for example, the luminosity distributions of clusters within rgc 3 kpc in giant galaxies should carry the strongest imprint of dynamical evolution ; direct observations could be straightforwardly made in many galaxies. larger samples of clusters taken from the rich virgo and fornax systems will reveal fine structure in the gclf and provide essential constraints on eventual theoretical modelling. and deep photometry of clusters in additional near - field galaxies should finally tell us how accurate gclfs can be as distance indicators. in addition, the brightest globulars in giant e galaxies may prove to be useful long - range standard candles. | | 3. | | it is possible that the globular clusters in central giant ellipticals such as m87 are the oldest visible objects in the universe. high - s / n spectra of them, compared with integrated spectra of milky way globulars and fitted with population synthesis codes, may lead to useful age determinations relative to the milky way halo and to stronger limits on the hubble time. | | 4. | | modern spectroscopic and imaging techniques are finally putting a complete and accurate understanding of the important m31 cluster system within reach. | | 5. | | the advent of large - format ccd arrays will enable us to study the large - scale structures of globular cluster systems far more quantitatively and accurately. | | 6. | | comprehensive radial velocity surveys


reach. | | 5. | | the advent of large - format ccd arrays will enable us to study the large - scale structures of globular cluster systems far more quantitatively and accurately. | | 6. | | comprehensive radial velocity surveys of gcss can place unique limits on the large - scale mass distribution of galaxies, and on the orbital characteristics of the halo clusters. for gcss at or beyond virgo - like distances, the velocity measurements do press the limits of current technology, but this field will be a rich mine for the new generation of 8 - meter - class telescopes to explore. | on the theoretical side, recommendations for future work may be easy to prescribe but will be hard to execute. a formation model specific enough to predict an initial cluster mass spectrum as a function of density and metallicity would be a major achievement. the dynamical evolution of gcss within galaxies of different types also needs to be modelled more comprehensively, with the eventual goal of predicting the full evolution of the gclf as a function of parent galaxy type and galactocentric distance. because they are virtually the only remaining witnesses to the long - vanished first epoch of galaxy formation, globular clusters stand among the most powerful cosmological probes that we have. although many intriguing new results and questions have emerged from the observational work of the past decade, we have also confirmed that globular cluster systems resemble each other rather closely. thus by extending our study of these remarkable objects, we are uncovering a common theme in the earliest history of the galaxies. it is a pleasure to give credit for projects, conversations, and ideas generated together over the years to many colleagues and friends, including david hanes, gretchen harris, hugh harris, jim hesser, chris pritchet, sidney van den bergh, malcolm smith, michael fall, and richard larson. the healthy state of our field today owes a great deal especially to the vision of rene racine, who in the 1970s first set in motion much of the work discussed above. i am pleased to acknowledge the hospitality of kitt peak national observatory, and d. and m. gehret of the orinda imac, as well as financial support from the natural sciences and engineering research council of canada.


in the depths of the mountainous jungle terrain of the macarena national park in southern colombia, hundreds of labourers toiled amid endless fields of coca bushes under a scorching sun. using their bare hands, they tore out the green coca plant – the main ingredient for cocaine – from its roots and destroyed it. surrounding them were dozens of armed soldiers deployed to protect them from possible guerrilla attacks. the oppressive sound of military helicopters hovering above filled the humid air. it took eight months for 900 labourers to destroy nearly 3, 000 of the 4, 600 hectares of coca in the park. the project was beset with problems from the start. the macarena national park and its surrounding area is the heartland of the farc guerillas – colombia ’ s largest guerrilla group. the risk of working in farc - controlled territory was great. the guerrillas ambushed government workers and soldiers in a bid to maintain their territorial control. over the months, workers resigned their jobs and deserted. the number of workers who dared to remain dwindled to around 200. the risk to their lives was simply not worth the humble wages, just $ 12 a day. since the start of the campaign bomb attacks and landmines placed by the guerrillas have killed 14 police and 8 contract workers. the mounting death toll forced the government to shift to more extreme methods of destroying coca – crop - spraying. duster planes, accompanied by military helicopters, are now flying low over the park ’ s jungle canopies spewing the toxic herbicide, which contains the controversial chemical glysophate. today colombia is the only country to use such crop - spraying methods in its war on drugs and also to do it in its own national parks. a recent editorial in colombia ’ s leading daily, el tiempo, was scathing : ‘ those who think that fumigating the macarena national park will bring an end to coca growing there are mistaken. there will be more coca and less of the national park. ’ ecuador shares a jungle border with its neighbour colombia and the ecuadorian authorities have repeatedly raised concerns over the environmental effects of spraying glysophate along their shared borders. the aerial fumigation of coca fields is staunchly supported by the us. it ’ s a profitable business and the bulk of contractors, herbicides, and duster planes originate in the us. despite decades of crop spraying, colombia remains the world ’ s leading producer of cocaine, supplying 90 per cent of the us market. environmentalists in and outside colombia fear that crop


left : cars in the bed of the derelict canal. right : the canal today, with the access to the falkirk wheel. by trevor timpson the forth and clyde canal was derelict for decades. its locks blocked up with rubbish, and wherever it interfered with road plans it was filled in and channelled through a pipe. it was seen only as a store of water for industry. now, with the industry mostly gone, scotland ' s first substantial canal lives on. not just reopened, but the setting for some of modern britain ' s most adventurous engineering works - and huge landmark art projects. on the site of an old tar plant stands the falkirk wheel, which raises boats 35 metres from the forth and clyde to the level of the union canal to edinburgh. half a million people visit it every year. just a start, say british waterways. ' can do attitude ' built from 1768 to 1790, the forth and clyde closed to navigation in 1963. campaigners began operating boats on it again from the 1970s. vessels were placed on stretches that no longer connected with each other, to arouse interest and deter development schemes. but jim mclachlan, chairman of the forth and clyde canal society said : " we seriously didn ' t expect the whole thing to be opened up in our lifetime. " nevertheless, gradually a new " can do " attitude grew up among british waterways management, he says - a desire to get the full value out of the waterway. then came the £84. 5m millennium link project, culminating in the opening of the two canals and the wheel by the queen in 2002. auchinstarry marina near kilsyth : a success story, says british waterways canal societies collected tens of thousands of signatures to prove to the lottery millennium commissioners that the plan to revive the link was not just a good project, but a " people ' s project ". when work on the millennium link began in the 1990s, there were 32 major obstructions across the forth and clyde canal. it cost £10m to reroute utility pipes laid in the canal after it closed to navigation. now, where boat building yards and foundries lined the canal banks, bluebells and bright yellow gorse bloom. in the old timber basins, swans guard their nests. where railway sidings carried coal wagons to the canal at kirkintilloch, a marina and residential development is open for business. and though strathclyde police have set sail on the canal on occasions to catch " groups involved in anti - social behaviour ",


andy scott says " the money ' s in the bank " for the kelpies, and the full - size statues are intended to be completed in 2011. but that is not enough for british waterways, andy scott and the forth and clyde. just east of maryhill, the east - west towpath is interrupted where the glasgow branch leaves the main canal. now, the planning application has gone in for a three - way bridge straddling the canal junction - supported by the towering bigman, a 30 - metre steel andy scott statue holding the supports in its outstretched hand like puppet strings. " for me it ' s got that thing about scale and pride and again some instance of the history of the canal and area, " says scott. the maryhill flight of locks from the kelvin aqueduct and still the plans pile up. in maryhill is a magnificent flight of locks, leading down to the sturdy aqueduct which takes the canal across the river kelvin. in the 1970s volunteers pulled 2, 000 tonnes of rubbish out of those same locks. now glasgow has ambitious plans for canoeing, caving and canyoneering courses down the incline beside them. and the city is also proposing a watersports centre at port dundas, the canal ' s glasgow terminus. then there is consideration of constructing access to loch lomond, close to the canal ' s western end. " there ' s been 40 years when development hasn ' t happened on it, " says richard millar. " and the opportunities that lie out there are tremendous. "


the start of school means it ’ s vaccine time, and a new 667 - page report released today from the institute of medicine should offer parents some reassurance. it found that there is no connection between the vaccine for measles, mumps, and rubella ( mmr ) and autism, despite some parent ’ s lingering concerns. and it said that other serious side effects of that and other childhood vaccines were rare. a committee of experts convened by the iom culled through more than 12, 000 peer - reviewed articles to examine whether eight childhood vaccines caused adverse events. the report specifically ruled out any causal relationship between the flu shot and bell ’ s palsy, and found that getting vaccinated against the flu doesn ’ t make asthma worse. it also dispelled any notions of a connection between the diptheria - tetanus - acellular pertussis ( dtap ) vaccine or the mmr vaccine and type - 1 diabetes. committee chair ellen wright clayton, professor of pediatrics and law at vanderbilt university, said in a statement : with the start of the new school year, it ' s time to ensure that children are up to date on their immunizations, making this report ' s findings about the safety of these eight vaccines particularly timely... the findings should be reassuring to parents that few health problems are clearly connected to immunizations, and these effects occur relatively rarely. and repeated study has made clear that some health problems are not caused by vaccines. the report found that only 14 specific health outcomes had convincing evidence linking them to vaccines — and most of those were rare. the committee ’ s findings about those side effects include : • the mmr vaccine can lead to fever - triggered seizures in some patients, but almost always without long - term consequences. it can also lead to a rare form of brain inflammation in some people with severe immune deficiencies. • the chickenpox vaccine ( varicella ) can cause brain swelling, pneumonia, hepatitis, meningitis, shingles and chicken pox in a minority of immunocompromised patients, as well as in some people with normal immune systems. • the mmr vaccine, and those for chicken pox, the flu, hepatitis b, meningitis, and tetanus, can trigger anaphylaxis, a serious allergic reaction that can appear shortly after injection. • injections of vaccines in general can trigger fainting and inflammation at the injection site. the committee also found links between the mmr vaccine


- dense and accessible patches of prey, as opposed to just more food options, is better for marine animals. - how different species are able to determine where the best patches of food sources are located is uncertain. marine animal populations thrive when presented with dense and accessible patches of prey, as opposed to just more of it, according to new research. it turns out that sheer abundance of food is less important than what scientists sometimes call " patchiness " — the spatial distribution of a food source. marine animals, from birds to dolphins, are able to home in on dense patches of food, making a more efficient use of precious energy for mealtime. " patchiness is not only ubiquitous in marine systems, it ultimately dictates the behavior of many animals and their relationships to the environment, " kelly benoit - bird, an oregon state university oceanographer, said in a statement. benoit - bird is the lead author of a study published this week in the journal biology letters. the research used sound waves to pinpoint the distribution of krill and other anchors of the food chain in waters near hawaii. the scientists found that the tiny crustaceans weren ' t uniformly distributed, but instead congregated in patches. this explained why two colonies of fur seals and seabirds were faring poorly but a third was healthy, the researchers said. " the amount of food near the third colony was not abundant, " benoit - bird said, " but what was there was sufficiently dense, and at the right depth. that made it more accessible for predation than the krill near the other two colonies. " the team also found that a type of bird that feeds on krill, called the thick - billed murre, was able to target the densest swarms of the tiny organisms. murres dove to an astonishing 650 feet ( 200 meters ) below the ocean ' s surface in search of their prey. " the murres are amazingly good at diving right down to the best patches, " benoit - bird said. it ' s not clear how the birds identify these feasts lurking deep beneath the surface of the ocean, she added. the team used sound waves not only to identify the gatherings of krill but to track murres, dolphins, squid and other animals. time and again, they found that by locating the densest clouds of phytoplankton, tiny ocean plants that are themselves a food source for krill, it was possible to figure out where these larger animals would gather. although the concept of " patchiness "


| a man looks at a satellite image of north korea ’ s nuclear test site in punggye - ri. ( yonhap news ) | north korea ’ s punggye - ri nuclear test complex is an ideal place to conduct underground atomic detonations due to its geological features and isolated location, south korean observers said. observers in the military and government said pyongyang selected the region and started constructing the site likely over two decades ago, although the certain date is not known. from the 1990s onward, the south korean and u. s. intelligence agencies have been closely observing the site. the site was used by the communist country to detonate its first and second nuclear tests in 2006 and 2009, with seoul predicting a third test can take place at anytime if the north ’ s leadership decides to take such a step. the north said late last month that it will build up its capability to deter aggression right after the u. n. security council passed a resolution condemning the dec. 12 launching of a long range rocket. the international community viewed the launch as a cover to test the country ’ s ballistic missile technology. local geologists said the region located in north hamgyeong province, kilju county has extensive granite bedrock formations that can help prevent radioactive materials from leaking to the surface following an atomic detonation. in addition, the site is located in the remote hamgyeong mountain range in the northeastern part of the country, and surrounded by high peaks such as the 2, 205 - meter - high mt. mantap and mt. hakmu. the mountain range has the largest number of high peaks on the korean peninsula and forms one of the natural barriers of north korea ’ s kaema plateau. north korean watchers said that pyongyang probably dug “ l - shaped ” tunnels for the two previous tests with the aims of preventing radiation leaks, although precautions taken ahead of the first detonation may have not prevented radioactive materials from escaping into the outside environment. the first test conducted in the eastern shaft may have used a straight horizontal tunnel connected to the vertical shaft that leads to the surface. this construction may have been inadequate to deal with the tremendous pressure and shock blast of a nuclear explosion. the second test carried out on the western shaft, on the other hand, may have used a spiral shaped horizontal shaft reinforced with barriers to contain the contamination, while the new southern tunnel probably has similar features. satellite images showed for some time that the isolationist country had completed work on a new shaft located south of


other hand, may have used a spiral shaped horizontal shaft reinforced with barriers to contain the contamination, while the new southern tunnel probably has similar features. satellite images showed for some time that the isolationist country had completed work on a new shaft located south of the 2006 and 2009 test areas, while tv footage that was released by south korea ’ s military earlier in the day showed the inside of a test tunnel with spiraling features and some 9 - 10 barriers captured in september 2010. the footage taken by the ( north ) korean central tv broadcasting station is probably of the latest tunnel. related to various features of the punggye - ri test site, the institute for science and international studies ( isis ) said in a report that the location of the instrumentation bunker, which can collect data from the test, is generally very similar to the ras koh complex used by pakistan for its 1998 nuclear test. the isis is a washington, d. c. - based non - profit think tank dedicated to informing the public about international security issues. intelligence also showed that while the eastern shaft used in the first test has been sealed off, there has been considerable activity in the new southern shaft and the western tunnel used for the second test almost four years ago. “ such activity can be seen as a sign that these shafts will be used for the next detonation test, ” a government insider, who did not want to identified, said. he said that seoul thinks that the western shaft may be used in the upcoming test, but policymakers have said that if the north decides to really test its weapons ability, both tunnels may be utilized. the north ’ s powerful national defense committee issued a warning on jan. 24 that it will conduct a “ high level ” test to show its nuclear deterrence capability. meanwhile, seoul has consistently warned the north that detonating another tunnel is the wrong move and will only worsen the situation. “ at this juncture, the right step for the north would be to listen to the international community and desist from another test, ” said unification ministry spokesman kim hyung - suk.


at my talk last night to the friends of sausal creek, i delivered a lot of information about the rock units exposed along shephard creek. for a while here i will post what i showed the crowd, starting at the bottom. the joaquin miller formation is a thick sequence of mostly shale, around 95 million years old ( late cretaceous epoch, specifically the cenomanian age ). it underlies nearly all the east side of the valley of palo seco creek, running into joaquin miller park. it weathers readily there, turning easily back into the clay it once was. this exposure is a roadcut at the intersection of scout and ascot drives. the beds are steeply tilted into the hillside, something that ’ s true of all the rocks in the canyon. and here ’ s a closeup. these rocks mostly crumble in the hand. toward the top of the unit, it gets more sandy ; an example is shown here from the bed of shephard creek. eventually it turns to straight sandstone and gets a new name, the oakland conglomerate ( here are three pages on that rock unit, 1 – 2 – 3 ). the joaquin miller formation was laid down far from land, but not very far. this is all brown clay that comes from continental sources, and the occasional sandy beds are evidence that underwater landslides could sometimes reach here. picture it way out in the gulf of mexico, where mississippi river mud can cascade down the continental slope for great distances.


david m. lane values of pearson ' s correlation, variance sum law, measures of variability the collection of data involves measurement. measurement of some characteristics such as height and weight are relatively straightforward. the measurement of psychological attributes such as self esteem can be complex. a good measurement scale should be both reliable and valid. these concepts will be discussed in turn. the notion of reliability revolves around whether you would get at least approximately the same result if you measure something twice with the same measurement instrument. a common way to define reliability is the correlation between parallel forms of a test. letting " test " represent a parallel form of the test, the symbol rtest, test is used to denote the reliability of the test. true scores and error assume you wish to measure a person ' s mean response time to the onset of a stimulus. for simplicity, assume that there is no learning over tests which, of course, is not really true. the person is given 1, 000 trials on the task and you obtain the response time on each trial. the mean response time over the 1, 000 trials can be thought of as the person ' s " true " score, or at least a very good approximation of it. theoretically, the true score is the mean that would be approached as the number of trials increases indefinitely. an individual response time can be thought of as being composed of two parts : the true score and the error of measurement. thus if the person ' s true score were 345 and their response on one of the trials was 358, then the error of measurement would be 13. similarly, if the response time were 340, the error of measurement would be - 5. now consider the more realistic example of a class of students taking a 100 - point true / false exam. let ' s assume that each student knows the answer to some of the questions and has no idea about the other questions. for the sake of simplicity, we are assuming there is no partial knowledge of any of the answers and for a given question a student either knows the answer or guesses. finally, assume the test is scored such that a student receives one point for a correct answer and loses a point for an incorrect answer. in this example, a student ' s true score is the number of questions they know the answer to and their error score is their score on the questions they guessed on. for example, assume a student knew 90 of the answers and guessed correctly on 7 of the remaining 10 ( and therefore incorrectly on 3 ). their true score would be 90 since that is the number


score is their score on the questions they guessed on. for example, assume a student knew 90 of the answers and guessed correctly on 7 of the remaining 10 ( and therefore incorrectly on 3 ). their true score would be 90 since that is the number of answers they knew. their error score would be 7 - 3 = 4 and therefore their actual test score would be 90 + 4. every test score can be thought of as the sum of two independent components, the true score and the error score. this can be written as : the following expression follows directly from the variance sum law : reliability in terms of true scores and error it can be shown that the reliability of a test, rtest, test, is the ratio of true - score variance to test - score variance. this can be written as : download pdf of derivation it is important to understand the implications of the role the variance of true scores plays in the definition of reliability : if a test were given in two populations for which the variance of the true scores differed, the reliability of the test would be higher in the population with the higher true - score variance. therefore, reliability is not a property of a test per se but the reliability of a test in a given population. assessing error of measurement the reliability of a test does not show directly how close the test scores are to the true scores. that is, it does not reveal how much a person ' s test score would vary across parallel forms of test. by definition, the mean over a large number of parallel tests would be the true score. the standard deviation of a person ' s test scores would indicate how much the test scores vary from the true score. this standard deviation is called the standard error of measurement. in practice, it is not practical to give a test over and over to the same person and / or assume that there are no practice effects. instead, the following formula is used to estimate the standard error of measurement. where smeasurement is the standard error of measurement, stest is the standard deviation of the test scores, and rtest, test is the reliability of the test. taking the extremes, if the reliability is 0 then the standard error of measurement is equal to the standard deviation of the test ; if the reliability is perfect ( 1. 0 ) then the standard error of measurement is 0. it is important to make measures as reliable as is practically possible. suppose an investigator is studying the relationship between spatial ability and a set of other variables. the higher the reliability of the test of spatial ability, the higher


standard error of measurement is 0. it is important to make measures as reliable as is practically possible. suppose an investigator is studying the relationship between spatial ability and a set of other variables. the higher the reliability of the test of spatial ability, the higher the correlations will be. similarly, if an experimenter seeks to determine whether a particular exercise regiment decreases blood pressure, the higher the reliability of the measure of blood pressure, the more sensitive the experiment. more precisely, the higher the reliability the higher the power of the experiment. power is covered in detail here. finally, if a test is being used to select students for college admission or employees for jobs, the higher the reliability of the test the stronger will be the relationship to the criterion. two basic ways of increasing reliability are ( 1 ) to improve the quality of the items and ( 2 ) to increase the number of items. items that are either too easy so that almost everyone gets them correct or too difficult so that almost no one gets them correct are not good items : they provide very little information. in most contexts, items which about half the people get correct are the best ( other things being equal ). items that do not correlate with other items can usually be improved. sometimes the item is confusing or ambiguous. increasing the number of items increases reliability in the manner shown by the following formula : where k is the factor by which the test length is increased, rnew, new is the reliability of the new longer test, and rtest, test is the current reliability. for example, if a test with 50 items has a reliability of. 70 then the reliability of a test that is 1. 5 times longer ( 75 items ) would be calculated as follows. which equals 0. 78. thus increasing the number of items from 50 to 75 would increase the reliability from 0. 70 to 0. 78. it is important to note that this formula assumes the new items have the same characteristics as the old items. obviously adding poor items would not increase the reliability as expected and might even decrease the reliability. more information on reliability from william trochim ' s knowledge source the validity of a test refers to whether the test measures what it is supposed to measure. the three most common types of validity are face validity, empirical validity, and construct validity. we consider these types of validity below. a test ' s face validity refers to whether the test appears to measure what it is supposed to measure. that is, does the test " on its face " appear to measure what it is supposed to


validity. we consider these types of validity below. a test ' s face validity refers to whether the test appears to measure what it is supposed to measure. that is, does the test " on its face " appear to measure what it is supposed to be measuring. an asian history test consisting of a series of questions about asian history would have high face validity. if the test included primarily questions about american history then it would have little or no face validity as a test of asian history. predictive validity ( sometimes called empirical validity ) refers to a test ' s ability to predict the relevant behavior. for example, the main way in which sat tests are validated is by their ability to predict college grades. thus, to the extent these tests are successful at predicting college grades they are said to possess predictive validity. construct validity is more difficult to define. in general, a test has construct validity if its pattern of correlations with other measures is in line with the construct it is purporting to measure. construct validity can be established by showing a test has both convergent and divergent validity. a test has convergent validity if it correlates with other tests that are also measures of the construct in question. divergent validity is established by showing the test does not correlate highly with tests of other constructs. of course, some constructs may overlap so the establishment of convergent and divergent validity can be complex. to take an example, suppose one wished to establish the construct validity of a new test of spatial ability. convergent and divergent validity could be established by showing the test correlates relatively highly with other measures of spatial ability but less highly with tests of verbal ability or social intelligence. reliability and predictive validity the reliability of a test limits the size of the correlation between the test and other measures. in general, the correlation of a test with another measure will be lower than the test ' s reliability. after all, how could a test correlate with something else as high as it correlates with a parallel form of itself? theoretically it is possible for a test to correlate as high as the square root of the reliability with another measure. for example, if a test has a reliability of 0. 81 then it could correlate as high as 0. 90 with another measure. this could happen if the other measure were a perfectly reliable test of the same construct as the test in question. in practice, this is very unlikely. a correlation above the upper limit set by reliabilities can


by gwen hill ms, rd, ld happy sweet potato month! sweet potatoes are what we consider a “ nutrient dense food. ” they are filled with many important nutrients that your body needs and are low in the nutrients you should limit. one medium sweet potato has only 100 calories, less than one gram of fat and 41 mg of sodium. yet it gives you a high amount of several important nutrients, including : fiber - 13 % of rda vitamin c - 25 % of rda vitamin a - 730 % of rda! all of these nutrients are important for different reasons. fiber helps our body regulate blood sugar, reduce bad cholesterol and stay regular. vitamin c is an important antioxidant, helps maintain our immune function and is a key player in collagen synthesis, which gives our skin its healthy and resilient qualities. though many great nutrients are found in this vegetable, vitamin a is the real star. sweet potatoes have a high amount of carotenoids, which are a precursor to vitamin a. carotenoids are responsible for the signature yellow / orange color - the deeper the color, the richer the level of carotenoids the veggie contains. vitamin a plays many roles in the body, including helping the body determine which white blood cells it needs to make in order to fight infection and other immune functions. it is also important for vision. vitamin a deficiency is the most significant cause of blindness in the developing world. eating nutrient dense foods, like sweet potatoes, will help improve your overall health. the recipe highlighted this week incorporates sweet potatoes into gnocchi. as a starchy vegetable, it is easy to see how this potato could provide necessary hearty components to this dish. enjoy the recipe after the jump! sweet potato gnocchi with fried sage and pine nuts adapted from gourmet 1 1 / 4 lb russet potatoes 1 ( 3 / 4 - lb ) sweet potato 1 large egg 1 / 2 tsp. grated nutmeg 1 / 3 cup grated parmigiano - reggiano cheese, plus more for serving 1 1 / 2 to 2 cups all - purpose flour, plus more for dusting 1 / 3 cup extra - virgin olive oil 1 cup sage leaves ( from 1 bunch ) 1 / 3 cup pine nuts, very thinly sliced 2 tbsp. unsalted butter 1. preheat oven to 450°f with rack in middle. 2. pierce russet and sweet potatoes in several places with a fork, then bake


3 cup pine nuts, very thinly sliced 2 tbsp. unsalted butter 1. preheat oven to 450°f with rack in middle. 2. pierce russet and sweet potatoes in several places with a fork, then bake in a 4 - sided sheet pan until just tender, 45 minutes to 1 hour. 3. cool potatoes slightly, then peel and force through ricer into sheet pan, spreading in an even layer. cool potatoes completely. 4. lightly flour 2 or 3 large baking sheets or line with parchment paper. 5. beat together egg, nutmeg, 1 tsp. salt, and 1 / 2 tsp. pepper in a small bowl. 6. gather potatoes into a mound in sheet pan, using a pastry scraper if you have one, and form a well in center. 7. pour egg mixture into well, then knead into potatoes. knead in cheese and 1 1 / 2 cups flour, then knead, adding more flour as necessary, until mixture forms a smooth but slightly sticky dough. dust top lightly with some of flour. 8. cut dough into 6 pieces. form one piece of dough into a 1 / 2 - inch - thick rope on a lightly floured surface. cut rope into 1 / 2 - inch pieces. gently roll each piece into a ball and lightly dust with flour. 9. repeat with remaining 5 pieces of dough. 10. turn a fork over and hold at a 45 - degree angle, with tips of tines touching work surface. working with one at a time, roll gnocchi down fork tines, pressing with your thumb, to make ridges on one side. transfer gnocchi as formed to baking sheets. fry sage leaves and pine nuts : 1. heat oil in a 12 - inch heavy skillet over medium heat until it shimmers. fry sage leaves in three batches, stirring, until they turn just a shade lighter and crisp ( they will continue to crisp as they cool ), about 30 seconds per batch. transfer to paper towels to drain. season lightly with salt. 2. fry pine nuts in three batches, stirring, until golden and crisp, about 30 seconds per batch. transfer to paper towels to drain. season lightly with salt. reserve oil in skillet. 1. add butter to oil in skillet with 1 / 2 tsp. salt and cook until golden - brown, 1 to 2 minutes. remove from heat. 1. add half of gnocchi to a pasta pot of well - salt


after the hurricane passed, some of the lilacs in my yard were lying on their sides with half their roots out of the ground. can i do something to save them? it ’ s best to leave the righting of large, heavy plants like trees to the professionals ( as well as the decision of whether or not a tree can be saved ). but straightening a toppled shrub is not difficult. do it now, while the soil is still soft from all the rain. all you have to do is firmly shove the shrub back into an upright position, then pound a few tall stakes vertically into the ground to keep it upright. position the stakes where they will provide support for the shrub ; you may need to tie branches to the stakes. try to protect the already compromised roots from further disturbance. if roots have been pulled out of the ground, you may need to carefully excavate a hole for them on the lilac ’ s upwind side. then replace the soil, burying the roots at the same depth they were before the storm. finish with a layer of organic mulch. ideally, the shrub should be secure enough so that another strong wind won ’ t rock the plant and tug on the root system. if the roots were damaged severely, consider pruning some of the top growth to compensate for the loss. selectively remove a few of the oldest stems, cutting them all the way to the ground. this practice, called renewal pruning, rejuvenates older lilacs and promotes better flowering, even when the shrub hasn ’ t been pushed over by a hurricane. — doug hall


betsy ' s plesiosaur, nichollsia borealis nichollsia borealis, one of the oldest and most complete plesiosaur fossils recovered in north america, and the oldest yet discovered from the cretaceous period, was uncovered in a syncrude canada ltd. mine near fort mcmurray, alberta, in 1994. two u of calgary scientists, dr. patrick druckenmiller and dr. anthony russell have named the 2. 6m long plesiosaur nichollsia borealis in memory of the late elizabeth ( betsy ) nicholls, former curator at the royal tyrrell museum of palaeontology. nicholls was a renowned palaeontologist who is credited with transforming the understanding of prehistoric ocean life by describing the largest - ever marine reptile, a 23 - metre - long ichthyosaur, discovered in northern british columbia in 1999. elizabeth ( betsy ) nicholls conducting field work in northeastern b. c. photo : rolex awards / tomas bertelsen. “ we chose this name because betsy was a key player in the study of marine reptiles, a mentor to me, a former student of tony, and a great person, ” said druckenmiller, who is now curator of earth sciences at the university of alaska museum of the north in fairbanks, alaska. “ we felt it was a fitting way to honour both her memory and her accomplishments in palaeontology. ” the fossil was discovered by machine operators greg fisher and lorne cundal in 1994 during routine mining operations at syncrude ’ s base mine, about 35 kilometres north of fort mcmurray near the athabasca river. amazingly, the specimen was serendipitously exposed by one of syncrude ’ s 100 - ton electric shovels approximately 60 metres below ground surface. it is complete except for its left forelimb and shoulder blade. nichollsia is also very significant because it fills a 40 - million - year gap in the plesiosaur fossil record and greatly increases the understanding of the ancient seaway that once split north america in two and whose shores abounded with dinosaurs. “ this individual was a pioneer in the marine waters that would eventually become the cretaceous western interior seaway, which ran the length of north america during much of the cretaceous and was home to one of the world ’ s most diverse communities of marine reptiles, ” druckenmiller said. “ it represents the oldest known forerunner of this amazing period in north american prehistory. ” nichollsia borealis is currently on display


constitutionalism : a skeptical view new york university school of law may 1, 2012 nyu school of law, public law research paper no. 10 - 87 this paper examines the ideology that goes by the name of " constitutionalism. " the first part of the paper considers the significance of " written constitutions " the second part of the paper casts a skeptical eye at conceptions of constitutionalisim that emphasize " limited " government. once " limited government " is contrasted carefully with " restrained government " ( restraints upon specific actions by government ) and with " controlled government " ( e. g. insistence upon democratic control ), we see that the association of constitutionalism with general limitations on the scope of government ought to make it a much more controversial ideal than the general anodyne acceptance of the term " constitutionalism " might lead us to expect. finally, the anti - democratic implications of constitutionalism are explored. the paper argues that, by insisting on limited government, constitutionalism downplays the important role that constitutions have to perform in the modern world in establishing and securing specifically democratic authority. number of pages in pdf file : 46 keywords : authority, constitution, constitutionalism, constitutional law, democracy, judicial review, limited government, rights, written constitutionaccepted paper series date posted : december 11, 2010 ; last revised : may 5, 2012 © 2013 social science electronic publishing, inc. all rights reserved. this page was processed by apollo4 in 0. 859 seconds


the other loving : uncovering the federal government ' s racial regulation of marriage rose cuison villazor hofstra university - maurice a. deane school of law new york university law review, vol. 86, p. 1361, 2011 hofstra univ. legal studies research paper no. 11 - 11 this article seeks to fill a gap in legal history. the traditional narrative of the history of the american racial regulation of marriage typically focuses on state laws as the only sources of marriage inequality. overlooked in the narrative are the ways in which federal laws also restricted racially mixed marriages in the decades before 1967 ( when the supreme court invalidated antimiscegenation laws in loving v. virginia ). specifically, during the american occupation of japan after world war ii, a combination of immigration, citizenship, and military laws and regulations led to restrictions on marriages along racial lines. these laws also converged to prevent married couples, many of whom were white american soldiers and local japanese women, from living in the united states together. accordingly, this article claims that the confluence of immigration, citizenship, and military laws functioned as a collective counterpart to state antimiscegenation laws. by unearthing this neglected history, this article seeks to deepen the conventional account of the public regulation of mixed marriages. as the article reveals, racial barriers to marriage were far more pervasive than previously acknowledged. contrary to the familiar chronicle, racial restrictions on marriage occurred through federal laws, were enforced by federal officials, took place beyond state borders, and effected distinct harms on interracial couples whose experiences have largely escaped legal and scholarly inquiry. recovering this lost history thus provides a more complete story of antimiscegenation regulation. moreover, it draws attention to the largely undertheorized role that immigration law played in preventing interracial marriages and provides insight into contemporary debates on federal involvement in marriage regulation. number of pages in pdf file : 79accepted paper series date posted : march 19, 2011 ; last revised : december 5, 2011 © 2013 social science electronic publishing, inc. all rights reserved. this page was processed by apollo7 in 0. 328 seconds