There was once a leak from Hebdomadal Council. The Assessor told her husband, who told my wife, who told me that Monday afternoon had been spent discussing what Lucas would say if various courses of action were adopted, leading to the conclusion that it would be best to do nothing. I was flattered, but a bit surprised. The tide of philosophical scepticism had ebbed, and it was generally allowed that a reasonable way of discovering what someone would say was to (...) ask him. Dick Southwood did: he would quiz me in Common Room – sometimes ending "Thank you for letting me bounce these ideas off you" – and had reliable information about how one member of Congregation would react to various proposals. And not only me: he was a listening Vice-Chancellor, who used to bike from Wellington Square to Merton for lunch, greeting many as he passed them, and ready to stop if occasion warranted it. Of course, there are many other leaks. I remember once attending a meeting in the Town Hall to argue for cycle tracks, and someone coming up to me, and saying, "You’re having a tussle with Council, aren’t you? I think you ought to see the minutes of their latest meeting"; the next day there was a copy in my pigeon hole, giving me just the ammunition I needed. What members of Congregation tend the forget is the existence – the other side of the green baize door, so to speak – of a corps of bedells. (shrink)
Some of my best friends are women, but I would not want my sister to marry one of them. Modern-minded persons criticize me for manifesting such out-dated prejudices, and would like to send me to Coventry for a compulsory course of reindoctrination. They may be right. It could conceivably be the case that in due course the Sex Discrimination Act will be tightened up, even to the extent of our recognizing that there are no ‘good reasons why the State should (...) not recognize contracts which are in all respects like marriage, except for the sex of the parties concerned’. We can envisage a society so enlightened that the relations between men and women will be purely platonic and it will be a matter of no concern whether two people are members of the opposite sex or not: or, alternatively, our feelings could be so completely homogenized, that it will make no difference to an emotional relationship whether Leslie and Julian have only one Y-chromosome between them, or two, or none at all. In that event I shall be shown to be wrong, and my critics entitled to erect a monument to female equality on my grave. But I have doubts, and suspect that long after I am dead men will go on falling in love with women and women will continue to find their hearts wooed and won by men. And this fact, if it is a fact, makes a profound difference to our social institutions. I want to follow out the logic of social differentiation, relying as little as I can on putative facts about the differences between the sexes. Scientifically attested knowledge is scarce in this field. Many academics take refuge in a safe suspension of judgment, but this is a craven dereliction of duty. We have yet to develop an adequate theory of knowledge in social matters, and only by thrashing out the apparently telling arguments on this and similar issues can we clear our minds about the nature of social knowledge. Moreover, if those who might argue rationally draw back from doing so, they leave the field clear for others who suffer from fewer inhibitions and fewer scruples. And finally, serious social consequences can follow from public confusion about the logic of a situation, and what things are possible and what desirable. There is a danger that in our attempts to remedy the real wrongs done to women we shall only succeed, as with much modern legislation, in making a bad case worse. (shrink)
Elijah foretold evil for Ahab in the name of the Lord. ‘I will bring evil upon you; I will utterly sweep you away, and will cut off from Ahab every male, bond or free in Israel’ … but when he heard those words, he rent his clothes, and put sackcloth upon his flesh, and fasted and lay in the sackcloth, and went about dejectedly. And the word of the Lord came to Elijah saying ‘Have you seen how Ahab has humbled (...) himself before me? Because he has humbled himself before me, I will not bring the evil in his days, but in his son's days I will bring evil upon his house.’. (shrink)
Volume three of Jaspers' Philosophy, which first appeared in German in 1932, contains his treatise on metaphysics with almost exclusive reference to the category of transcendence. In Jaspers' thought freedom aims at unconditional validity, and the realization of unconditionality can occur only in relation to transcendence. The appearance of transcendence is a phenomenon of historicity. Jaspers elaborates the meaning of transcendence in terms of formal transcending, existential relations to transcendence and in the reading of ciphers of transcendence. Formal transcending is (...) to aim at being itself. Jaspers thematizes upon those principles which attempt to discover being itself: a development from the thinkable to the unthinkable, the dialectics of transcending in thought, transcending beyond subject and object, three spheres of transcending along categorial lines. Jaspers devotes a substantial inquiry into the notion of transcendence relative to the categories of objectivity, reality and freedom. He recognizes that transcendence cannot be forced upon one's Existenz. Rather "transcendence manifests itself in my own attitude toward it. I grasp its being in the inner action that makes me myself; its hand is offered to me as I take it." The recognition of transcendence arises in existential boundary situations which Jaspers identifies by a kind of phenomenology of defiance and surrender, rise and fall, diurnal law and nocturnal passion, the wealth of diversity and the one. The final portion of the book deals with the reading of ciphers. A cipher is the language of transcendence, although it is not a communication that can be readily understood or even heard in consciousness at large. "It is only in the absolute consciousness of Existenz that a direct language of transcendence is truly, substantially present." Jaspers admits that ciphers of transcendence are ambiguous for the precise reason that the symbol is inseparable from that which it symbolizes. Consequently, even though ciphers bring transcendence to mind, because of the inseparable union between the symbol and the symbolized, there is no interpreting of ciphers. Jaspers develops the thesis that Existenz is the place of reading ciphers. Alluding toward the end of his metaphysics to the arguments for the existence of God, Jaspers affirms that the arguments over the course of history have floundered because transcendence is not as such. "No empirical determination and no cogent inference can assure us that there is transcendence at all. Transcendent being is encountered in transcending, but it is neither observed nor conceived."--J. R. (shrink)
David Lewis criticizes an argument I put forward against mechansim on the grounds that I fail to distinguish between OL, Lucas's ordinary potential arithmetic output, and OML, Lucas's arithmetical output when accused of being some particular machine M; and correspondingly, between OM the ordinary potential arithmetic output of the machine M, and ONM, the arithmetic output of the machine M when accused of being a particular machine N. For any given machine, M, N, O, P, Q, R,... etc., I can (...) in principle calculate a Godel sentence for that machine - indeed infinitely many, depending on the Godel numbering scheme adopted. The Godel sentence of a particular machine can, I claim, be seen to be true, if that machine is adequate for Elementary Peano Arithmetic. Hence, if I were accused of being M, I can on that supposition see that the Godel sentence of M is true, since I am capable of Elementary Peano Arithmetic and the machine M is said to be an adequate characterization of me. (shrink)
It seems to me certain that the perception of foreign bodies of a certain sort, although a necessary, is not the only, part of the basis of our belief in other persons. The greatest disagreement with this view that I know of has been expressed by Professor Aaron in a paper published in Philosophy , XIX, 72. He claims that, since one does not really know “what it means to be a mind in one's own case,” the question whether we (...) can be certain that there are other minds is meaningless except as reducible to the question whether such propositions as “Robinson exists” are propositions which we can be certain about. And he tries to show that no more is involved in the analysis of “Robinson exists” than would be involved in the analysis of propositions of whose truth we can be perceptually certain, such as “That table over there exists” or “The Eiffel Tower exists.” My assurance that Robinson exists is not the assurance that something called Robinson's mind exists. It is the perfectly ordinary perceptual assurance that ‘the person over there’ exists. “You ask me how I am certain that Robinson exists and I answer, ‘Well, look, there he is.’ It would be absurd for anyone to say that he does not exist when I see him here before me and hear him talk and watch him move that chair.”. (shrink)
x10.1 Locality Newton's Law of Universal Gravitation was always open to the complaint that it involved \Action at a Distance", contrary to the Principle of Locality. But it was very well established empirically, and had to be accepted. Similarly in contemporary quantum me- chanics we seem to have correlations between measurements that defy the Principle of Locality, but have to be accepted none the less.1 Although locality is a characteristic mark of causal con- nexion, it is not, as Hume supposed,2 (...) an essential one. Nor is it merely a uniformity we have found to hold for the most part|else we should feel little compunction in accepting that in some cases it happened not to hold. It is clearly an a priori principle, though not an absolutely necessary one. (shrink)
I must start with an apologia. My original paper, ``Minds, Machines and Gödel'', was written in the wake of Turing's 1950 paper in Mind, and was intended to show that minds were not Turing machines. Why, then, didn't I couch the argument in terms of Turing's theorem, which is easyish to prove and applies directly to Turing machines, instead of Gödel's theorem, which is horrendously difficult to prove, and doesn't so naturally or obviously apply to machines? The reason was that (...) Gödel's theorem gave me something more: it raises questions of truth which evidently bear on the nature of mind, whereas Turing's theorem does not; it shows not only that the Gödelian well-formed formula is unprovable-in-the-system, but that it is true. It shows something about reasoning, that it is not completely rule-bound, so that we, who are rational, can transcend the rules of any particular logistic system, and construe the Gödelian well-formed formula not just as a string of symbols but as a proposition which is true. Turing's theorem might well be applied to a computer which someone claimed to represent a human mind, but it is not so obvious that what the computer could not do, the mind could. But it is very obvious that we have a concept of truth. Even if, as was claimed in a previous paper, it is not the summum bonum, it is a bonum, and one it is characteristic of minds to value. A representation of the human mind which could take no account of truth would be inherently implausible. Turing's theorem, though making the same negative point as Gödel's theorem, that some things cannot be done by even idealised computers, does not make the further positive point that we, in as much as we are rational agents, can do that very thing that the computer cannot. I have however, sometimes wondered whether I could not construct a parallel argument based on Turing's theorem, and have toyed with the idea of a von Neumann machine. A von Neumann machine was a black box, inside which was housed John von Neumann.. (shrink)
In Epiphany Term, 1942, C.S. Lewis delivered the Riddell Memorial Lectures in the Physics Lecture Theatre, King's College, Newcastle, which was then a constituent college of the University of Durham. The Riddell Memorial Lectures were founded in 1928 in memory of Sir John Buchanan Riddell of Hepple, onetime High Sheriff of Northumberland, who had died in 1924. His son, Sir Walter, was, like his father, a devout Christian, active throughout his life in public affairs. He was Fellow, and subsequently Principal, (...) of Hertford College, Oxford, and Secretary, and subsequently Chairman, of the University Grants Committee---at a time when the interventions of the UGC in academic affairs were entirely benign. I myself have a special personal interest in the founder of the Riddell Lectures. Sir Walter and my father were contemporaries at Oxford and close friends. Owing to his untimely death I never knew him, though I am credibly assured that he must have viewed me when I was taken to Hepple in a Moses' basket at the age of six months. In being invited to give this lecture on the Riddell Lectures, I am not only honoured but enabled to discharge a debt of family.. (shrink)
*This work is no longer under development* Two major themes in the literature on indicative conditionals are that the content of indicative conditionals typically depends on what is known;1 that conditionals are intimately related to conditional probabilities.2 In possible world semantics for counterfactual conditionals, a standard assumption is that conditionals whose antecedents are metaphysically impossible are vacuously true.3 This aspect has recently been brought to the fore, and defended by Tim Williamson, who uses it in to characterize alethic necessity by (...) exploiting such equivalences as: A⇔¬A A. One might wish to postulate an analogous connection for indicative conditionals, with indicatives whose antecedents are epistemically impossible being vacuously true: and indeed, the modal account of indicative conditionals of Brian Weatherson has exactly this feature.4 This allows one to characterize an epistemic modal by the equivalence A⇔¬A→A. For simplicity, in what follows we write A as KA and think of it as expressing that subject S knows that A.5 The connection to probability has received much attention. Stalnaker suggested, as a way of articulating the ‘Ramsey Test’, the following very general schema for indicative conditionals relative to some probability function P: P = P 1For example, Nolan ; Weatherson ; Gillies. 2For example Stalnaker ; McGee ; Adams. 3Lewis. See Nolan for criticism. 4‘epistemically possible’ here means incompatible with what is known. 5This idea was suggested to me in conversation by John Hawthorne. I do not know of it being explored in print. The plausibility of this characterization will depend on the exact sense of ‘epistemically possible’ in play—if it is compatibility with what a single subject knows, then can be read ‘the relevant subject knows that p’. If it is more delicately formulated, we might be able to read as the epistemic modal ‘must’. (shrink)
In his illuminating discussion of ‘the Caspian question’ Sir William Tarn, basing his case mainly on Aristotle, Meteorologica, 2. 1. 10 and Strabo, 11. 7. 4, argued that Alexander knew of the existence of the Aral Sea. Tarn's conclusion, however, was soon challenged by Professor Lionel Pearson, who disagreed in particular with Tarn's interpretation of the passage in Strabo. But, although he undoubtedly succeeds in showing that some of Tarn's arguments are not valid, Pearson fails, as it seems to me, (...) to disprove his main contention. Indeed, Pearson misunderstands the line of Strabo's argument and is led to propose an unnecessary emendation of the text. (shrink)
I thank Professor Otteson for his review of Escape from Leviathan (EFL). His exposition of what I wrote is relatively accurate. I shall here do my best to correct any misunderstandings and reply to his welcome criticisms, ignoring our various points of agreement and his generous praise.
Measures of student ethical sensitivity and their increases help to answer questions such as whether accounting ethics should be taught at all. We investigate different sensitivity measures and alternatives to the well-established Defining Issues Test (DIT-2, Rest, J. R. et al. [1999, Postconventional Moral Thinking: A Neo-Kohlbergian Approach (Lawrence Erlbaum Associates, Mahwah, NJ]), frequently used to measure the effects of undergraduate accounting ethics education. Because the DIT measures cognitive development, which increases with age, the DIT scores for younger accounting students (...) are typically lower, have limited range, and are not likely to vary sufficiently with corresponding choices in ethical dilemmas. Since the DIT measures only the moral judgment component of ethical decision-making, we consider the multidimensional ethical scale (MES) to allow respondents to provide explanations for their moral and other judgments. The MES has been used to measure attitudes related to justice, utility, contractualism, egoism, and relativism. Unfortunately, the MES is not comparable in one-dimension to the DIT, and unlike the DIT, the MES has no theoretical or objective base. Therefore, we construct a comparable one-dimensional relative measure, a Composite MES Score, obtained from previous research on practicing accountants. We compare the reliability of this measure to the DIT in explaining the ethical choices of 54 specially chosen, somewhat homogeneous students, whose ages range from 18 to 19, and who are taking a second semester freshman accounting course at a private, religion-affiliated university. These particular students are relatively untrained in the formal use of questionable accounting choices. These students are less likely to recognize the dilemmas of the MES and are also less likely to demonstrate sufficient variation in their DIT scores, traditionally low for freshmen students. As freshmen, they are recent graduates of high school and more likely guided by other ethical influences including friends, family, or contractual obligations (some of the MES constructs) rather than higher cognitive development. This study confirms suspicions. We find the DIT scores do not vary sufficiently to explain the moral reasoning of freshmen. For eight dilemmas and 24 choices we find the DIT score correlates with only three choices, whereas the MES regression models have at least one significant construct for 23 out of 24 ethical choices. The Composite MES Score (a relative measure) also explains 23 out of 24 choices and is statistically related to the DIT in only one of the choices. Unlike the DIT, the Composite MES permits pretest and retesting with different dilemmas to evaluate changes in ethical sensitivity. These results argue for relative rather than absolute measures of sensitivity and guides beyond cognitive development (the DIT-score) to explain undergraduate student sensitivity. (shrink)
After his refutation of the doubts concerning Proposition I.7, Ibn al-Haytham mentions three possible ways in which circles may intersect, submitting them to the following “intuitive” argument: one part of one of the two circles is situated inside of the other circle, and its other part is situated outside of it. One is therefore tempted to believe that the commentator accepts the principle of continuity in the case of circles, since his argument has the following meaning: if a circle is (...) divisible into two parts, one of which is situated inside the other circle, and the other outside of it, then the two circles cut one another. The author of this article proposes to establish the limits of this belief, on the basis of the following reflections: 1). It will be noted first of all that what could be called the ‘principle of the intersection of circles’ does not constitute ipso facto a principle in the mind of Ibn al-Haytham: no allusion is made to it in the commentary on Proposition I.1, among others. 2) It will be established later on that if one accepts that a line is the result of the movement of a point, the principle of continuity should be considered by him as something which is obvious by itself, without being stated. This conclusion will be based on an analysis of the notion of continuity in its classical meaning, and on Ibn al-Haytham’s commentary on Proposition X.1. 3) On the other hand, we should note the presence of a ‘sketch’ of topological language, which Ibn al-Haytham develops for the notion of a circle : one could say in this context that his reflection constitutes an important, if not principal, stage in the process which was to lead to the explicit formulation of the principle of continuity. (shrink)
It is a pleasure for me to give this opening address to the Royal Institute of Philosophy Conference on ‘Explanation’ for two reasons. The first is that it is succeeded by exciting symposia and other papers concerned with various special aspects of the topic of explanation. The second is that the conference is being held in my old alma mater , the University of Glasgow, where I did my first degree. Especially due to C. A. Campbell and George Brown there (...) was in the Logic Department a big emphasis on absolute idealism, especially F. H. Bradley. My inclinations were to oppose this line of thought and to espouse the empiricism and realism of Russell, Broad and the like. Empiricism was represented in the department by D. R. Cousin, a modest man who published relatively little, but who was of quite extraordinary philosophical acumen and lucidity, and by Miss M. J. Levett, whose translation of Plato's Theaetetus formed an important part of the philosophy syllabus. (shrink)
I am going in this lecture on ‘Philosophy and Practice’ first to say something about philosophy and then something about practice, in order to show you how they bear on one another. But I must start by paying a tribute to the President of the Society for Applied Philosophy, Professor Sir A. J. Ayer, who has kindly agreed to take the chair at this lecture. I can honestly say that he is more responsible than anybody else for putting me on (...) the right track in moral philosophy. He did this by convincing me, when young, that the ways people were doing it at that time had no future. In the famous chapter on ethics in his marvellously readable and exciting book, Language, Truth and Logic , Ayer was thought to be trying to show that moral philosophy itself, and perhaps even ordinary first-order moral thinking, was a waste of time. From later work of his, and from his occasional pronouncements about moral and political questions, it is evident that the second of these slanders was false. But even on the theoretical side the lessons I learnt from his book were positive as well as negative. That is not to say that the negative lessons were unimportant. Some people have still not absorbed them, and continue to waste our time. But here are two positive points which you will find in Ayer's book, and which for me were crucia. (shrink)
I am very pleased to see the response by J S Taylor to my critique of the “organs debate”. He makes some notable and important points, but also some errors to which attention should be drawn.Taylor erroneously attributes to me concern that the organ debate excessively focuses on saving the lives of a few people. My concern was about the narrow framework within which the debate is embedded and that it focuses on the lives of a few privileged people—those who (...) can pay—while largely neglecting the lives of those who cannot. The fact that some attention has been paid to such issues in some journals does not negate the importance of my claim. Moreover, it is not that the question of millions of premature deaths has …. (shrink)
Equality in the present age has become an idol, in much the same way as property was in the age of Locke. Many people worship it, and think that it provides the key to the proper understanding of politics, and that on it alone can a genuinely just society be reconstructed. This is a mistake. Although, like property, it is a useful concept, and although, like property, there are occasions when we want to have it in practice, it is not (...) a fundamental concept any more than property is, nor can having it vouchsafe to us the good life. In an earlier paper I argued against equality by showing that the concept of equality was confused and that many of the arguments i egalitarians adduced were either invalid or else supported conclusions I which were not really egalitarian at all. Many egalitarians, however, have complained that my arguments were not fair, because I had failed to elucidate the concept adequately, or because the position I attacked was not one that any egalitarian really wished to maintain, or because I had overlooked other arguments which were effective in establishing egalitarian conclusions, or because the positive counter-arguments of my own I put forward more as a matter of taste than of serious political commitment. In this paper, therefore, I want to elucidate the concept more fully, concede what I should to my critics, point out that, even so, their conclusions do not follow, and give further reasons not only for supposing that egalitarian arguments are invalid but for discerning positive merits in some forms of inequality. (shrink)
C I Lewis showed up Down Under in 2005, in e-mails initiated by Allen Hazen of Melbourne. Their topic was the system Hazen called FL (a Funny Logic), axiomatized in passing in Lewis 1921. I show that FL is the system MEN of material equivalence with negation. But negation plays no special role in MEN. Symbolizing equivalence with → and defining ∼A inferentially as A→f, the theorems of MEN are just those of the underlying theory ME of pure material equivalence. (...) This accords with the treatment of negation in the Abelian l-group logic A of Meyer and Slaney (Abelian logic. Abstract, Journal of Symbolic Logic 46, 425–426, 1981), which also defines ∼A inferentially with no special conditions on f. The paper then concentrates on the pure implicational part AI of A, the simple logic of Abelian groups. The integers Z were known to be characteristic for AI, with every non-theorem B refutable mod some Zn for finite n. Noted here is that AI is pre-tabular, having the Scroggs property that every proper extension SI of AI, closed under substitution and detachment, has some finite Zn as its characteristic matrix. In particular FL is the extension for which n = 2 (Lewis, The structure of logic and its relation to other systems. The Journal of Philosophy 18, 505–516, 1921; Meyer and Slaney, Abelian logic. Abstract. Journal of Symbolic Logic 46, 425–426, 1981; This is an abstract of the much longer paper finally published in 1989 in G. G. Priest, R. Routley and J. Norman, eds., Paraconsistent logic: essays on the inconsistent, Philosophica Verlag, Munich, pp. 245–288, 1989). (shrink)
Plato was the first feminist. In the Republic he puts forward the view that women are just the same as men, only not quite so good. It is a view which has often been expressed in recent years, and generates strong passions. Some of these have deep biological origins, which a philosopher can only hope to recognize and not to assuage. But much of the heat engendered is due to unnecessary friction between views which are certainly compatible and probably correct. (...) And here a philosopher can help. If we can divide the issues neatly, at the joints, then we need not quarrel with one another for saying something, probably true, because what is being maintained is misconstrued and taken to mean something else, probably false. (shrink)
It is a pleasure for me to give this opening address to the Royal Institute of Philosophy Conference on ‘Explanation’ for two reasons. The first is that it is succeeded by exciting symposia and other papers concerned with various special aspects of the topic of explanation. The second is that the conference is being held in my old alma mater, the University of Glasgow, where I did my first degree. Especially due to C. A. Campbell and George Brown there was (...) in the Logic Department a big emphasis on absolute idealism, especially F. H. Bradley. My inclinations were to oppose this line of thought and to espouse the empiricism and realism of Russell, Broad and the like. Empiricism was represented in the department by D. R. Cousin, a modest man who published relatively little, but who was of quite extraordinary philosophical acumen and lucidity, and by Miss M. J. Levett, whose translation of Plato's Theaetetus formed an important part of the philosophy syllabus. (shrink)
Whatever good or ill it did to Guy Fawkes, his resuscitation at the hands of Bernard Williams has, by any utilitarian reckoning, been a Good Thing. A casual glance at the literature that has accumulated over the past thirty-five years leaves no doubt that the topic has been reduplicated many times over, to the great enjoyment of undergraduates, who have been able to write science fiction under the guise of essays in the Philosophy of Mind, and of dons, who in (...) an age of cvs and Assessments, have been able to notch up page after page of counter-replies to replies to rebuttals of previous papers, not to mention an often welcome tally of references in the citation index. But the actual arguments adduced by Williams can be turned to support a much more traditional view of the self, as a necessarily unique agent whose individuality is established by his capacity for autonomous action. (shrink)
The critics have not been generous towards Valerius Flaccus' Argonautica as a whole, but their praise of his Medea episode, whether moderate or immoderate, has been fairly unanimous. W. C. Summers writes: ‘Valerius manages to treat the same theme with originality and power; in psychological probability his version seems to me superior to anything that has reached us from antiquity’. And J. M. K. Martin: ‘Where he displayed the most distinct originality, where he parted company with the Alexandrian poet with (...) greatest advantage to himself and his readers, is in the treatment of the episode of Medea and Jason’. Earlier articles of mine have endeavoured to illustrate Valerius' basic originality, i.e. that, however much he takes over from others, the final product is something new and distinctive. (shrink)
Responsibility is a key concept in our moral, social, and political thinking, but it is not itself properly understood. J.R. Lucas here presents a lively, broad, and accessible discussion of responsibility in various areas of human life, from personal and sexual relations to politics.
In ‘Minds, Machines and Gödel’, 1961, J. R. Lucas proposed that Godel's theorem made possible a refutation of mechanism—the thesis that mind is wholly comprehensible as a consistent, rule-governed machine. A sympathetic reading of Lucas's argument might run something as follows: ‘If I am a machine then it will be possible in principle to give a specification of the consistent formal system, L, that represents me. If this formal system were handed to me, I would be able to prove a (...) Gödel sentence, G, which L could not generate—that is, L could not model my proving G. But since I have proved G, L is inadequate as a model of my cognitive process.’. (shrink)
I am going in this lecture on ‘Philosophy and Practice’ first to say something about philosophy and then something about practice, in order to show you how they bear on one another. But I must start by paying a tribute to the President of the Society for Applied Philosophy, Professor Sir A. J. Ayer, who has kindly agreed to take the chair at this lecture. I can honestly say that he is more responsible than anybody else for putting me on (...) the right track in moral philosophy. He did this by convincing me, when young, that the ways people were doing it at that time had no future. In the famous chapter on ethics in his marvellously readable and exciting book,Language, Truth and Logic, Ayer was thought to be trying to show that moral philosophy itself, and perhaps even ordinary first-order moral thinking, was a waste of time. From later work of his, and from his occasional pronouncements about moral and political questions, it is evident that the second of these slanders was false. But even on the theoretical side the lessons I learnt from his book were positive as well as negative. That is not to say that the negative lessons were unimportant. Some people have still not absorbed them, and continue to waste our time. But here are two positive points which you will find in Ayer's book, and which for me were crucia. (shrink)
In this article, Lucas maintains the falseness of Mechanism - the attempt to explain minds as machines - by means of Incompleteness Theorem of Gödel. Gödel’s theorem shows that in any system consistent and adequate for simple arithmetic there are formulae which cannot be proved in the system but that human minds can recognize as true; Lucas points out in his turn that Gödel’s theorem applies to machines because a machine is the concrete instantiation of a formal system: therefore, for (...) every machine consistent and able of doing simple arithmetic, there is a formula that it can’t produce as true but that we can see to be true, and so human minds and machines have to be different. Lucas considers as well in this article some possible objections to his argument: for any Gödelian formula we could, for instance, construct a machine able to produce it or we could put the Gödelian formulae that we had proved as axioms of a further machine. However - as Lucas underlines - for every of such machines we could again formulate another Gödelian formula, the Gödelian formula of these machines, that they are not able to proof but that we can recognize as true. More general arguments, such as the possibility to escape Gödelian argument by suggesting that Gödel’s theorem applies to consistent systems while we could be inconsistent ones, are moreover refuted by Lucas by maintaining that our inconsistency corresponds to occasional malfunctioning of a machine and not to his normal inconsistency; indeed, a inconsistent machine is characterized by producing any statement, on the contrary human being are selective and not disposed to assert anything. (shrink)
