Timothy Williamson is a principal architect of necessitism, the claim that everything that exists necessarily exists. Ontology is necessary. Things could not have been otherwise. The universe could not have evolved differently. Necessitism is opposed to the idea of contingency, which denies that necessarily everything that is something is necessarily something. Ontology is contingent. Things could have been otherwise. There is ontological chance in the universe. Possibilities exist. Necessitism grows out of the introduction of modal logic into quantification theory by Ruth Barcan Marcus in 1947, in which she proved the necessity of identity. Before Marcus, most philosophers limited the necessity of identity to self-identity. Since her work, David Wiggins in 1965 and Saul Kripke in 1971 have suggested there is no contingent identity. Williamson reads Barcan Marcus as proving that everything is necessarily what it is, everything that exists necessarily exists. Williamson writes her argument as
The logical arguments for the necessity and permanence of identity are straightforward, and widely accepted in at least some form. Suppose that x is identical with y. Therefore, by the indiscernibility of identicals, x is whatever y is. But y is necessarily identical with y. Therefore x is necessarily identical with y. By analogous reasoning, x is always identical with y. More strongly: necessarily always, if x is identical with y then necessarily always x is identical with y. Of course, we understand ‘x’ and ‘y’ here as variables whose values are simply things, not as standing for definite descriptions such as ‘the winning number’ that denote different things with respect to different circumstances.There is a serious flaw in the reasoning that
“x is whatever y is. But y is necessarily identical with y. Therefore x is necessarily identical with y.”Wiggins and Kripke also made this error. The proper reasoning is
“x has the same properties as y. But y is necessarily self-identical with y. Therefore x is necessarily self-identical, i.e., with x.”Numerically distinct objects cannot have identical extrinsic external information, the same relations to other objects in their neighborhood, the same positions in space and time, unless they are one and the same object. Now Barcan Marcus is correct if she can be understood as talking about a universe of discourse described by first-order logic. As Rudolf Carnap proposed, the first-order object language can be analyzed for truth values of propositional functions in a second order meta-language. But these are literally just "ways of talking." And information philosophy is an attempt to go "beyond logic and language." Propositions that are perfectly substitutable in quantified modal logic contexts are indeed necessarily identical. But there are no numerically distinct material objects that are perfectly identical. Information philosophy shows that numerically distinct objects can have a relative identity if their intrinsic internal information is identical. Information philosophy has also established the existence of metaphysical possibility in two ways. The first is quantum mechanical indeterminacy. The second is the increasing information in the cosmological and biological universe. There can be no new information without possibilities, which depend on ontological chance. Since information philosophy has shown that the increase in information in our universe is a product of chance events, without possibilities there can be no new information created. In our metaphysics, ontology is irreducibly contingent. Nothing is necessary.
Excerpts from Towards a reasonable libertarianism1
One of the many reasons, I believe, why philosophy falls short of a satisfying solution to the problem of freedom is that we still cannot refer to an unflawed statement of libertarianism. Perhaps libertarianism is in the last analysis untenable. But if we are to salvage its insights, we certainly need to know what is the least unreasonable statement the position could be given. Compatibilist resolutions to the problem of freedom2 must wear an appearance of superficiality, however serious or deep the reflections from which they originate, until what they offer by way of freedom can be compared with something else, whether actual or possible or only seemingly imaginable, which is known to be the best that any indeterminist or libertarian could describe.
A sympathetic and serviceable statement of libertarianism cannot be contrived overnight, nor can it be put into two or three sentences, which is all that some utilitarian and compatibilist writers have been willing to spare for the position. If they were more anxious to destroy or supersede libertarianism than to understand and improve it, this was natural enough; but time or human obstinacy have shown that the issue is too complex for such summary treatment. What follows is offered as a small step in the direction of a more reasonable exposition. It concentrates on two or three points, where many need attention. If the treatment of these two or three points has the final effect of making the position even less credible, or of making me sacrificial scapegoat for oddities which persist, I still hope to have shown that the libertarian perceived something which was missed by all extant compatibilist resolutions of the problem of freedom; and that the point the libertarian was making must bear upon any future reconstruction of our notions and practices. I What the libertarian means by 'He could have done otherwise' The libertarian insists that a man is only responsible or free if sometimes he could do otherwise than he does do. It must be genuinely up to him what he chooses or decides to do. But what does this mean? Let us begin with three clarifications. (i) It is characteristic of the libertarian to insist that for at least some of the things which the man with freedom does, or plans, or decides to do, he must have a genuine alternative open to him. That is, for some action A and some action B, where A ≠ B, he must be able to do A and he must be able to do B. But does the same apply to what the man with freedom thinks, what he believes, and what he infers?3 In another place,4 I have given an argument, whatever it may be worth, whose purpose was to show that the notions open choice, decision, alternative, up to me, freedom have a different point in the realm of belief, the state whose distinctive aspiration it is to match or represent the world as it is, from their point in the realm of action and volition. For of action and volition the proper province is not to match anything in the physical world but to affect or act upon the world. The world and its causal properties, whether or not these constitute it a deterministic world, are the unarguable framework within which action takes place; but for the libertarian it is typical and proper to insist that nothing in that world should completely determine the ends, objectives and ideals with which the free agent, if he is truly free, deliberates to change that world. There is no question of requiring of ends and ideals some correspondence with, some sentence-like satisfaction by, the things in the world. (If the onus were anywhere then, as Miss Anscombe has suggested, it would have to be the other way about.) The libertarian ought, on the other hand, to be content to allow the world, if it will only do so, to dictate to the free man how the world is.5 Freedom does not consist in the exercise of the (colourable but irrelevant) right to go mad without interference or distraction by fact.6 Alternatives of the kind which the libertarian defines and demands are alternatives in the realm not of theory but of practice.(ii) To say that an agent is doing B or will do B and not A, and that there is something else, A, which he can do, is to say something ambiguous, even though (ignoring permissive and epistemic contexts) 'can' itself is most likely univocal (see (iii) below). A may be something the agent can generally do, for instance, or something he can for such and such a stretch of time do, given the opportunity. It is true and important that the latter claim is confirmed if the agent's wanting or trying to do A at an appropriate moment during that period is a sufficient condition of his producing a non-fluke performance of A. But read in this way he can do otherwise is irrelevant to what concerns the libertarian. What organises the whole dispute, and what holds the libertarian's position apart from his present day opponents' position, is rather his treatment of another question: if physical determinism is true, is there ever something different from what the agent will in fact do at some time ti such that the agent can at ti do that other thing at ti instead? If physical determinism is true, then the libertarian maintains that such an alternative is never really or truly available to the agent (see Section III). Sometimes earlier actions do completely determine successions of later events and actions. According to the libertarian, however, there can only be true alternatives if there are at least some movements or actions or mental events which, whether or not they completely determine their immediate successors, are not themselves entirely determined by some predecessor. (Of course, this is only a necessary condition of alternatives or freedom of action.) He readily allows that even if there were not such successions, we could, if we wished to ignore all sorts of relevant facts, mechanically continue to draw our conventional distinctions between different kinds of situations - between acting voluntarily and acting reluctantly, between control and non-control, between freedom and constraint. But determinism undermines their whole point, he says. It whittles away too much that is important from the notion of responsibility. It transforms it out of recognition. True freedom cannot be maintained by holding onto distinctions for which there is no factual backing or consistent rationale. (iii) Though the sentence schemata he could have done otherwise and he could have done A instead of B may be used with varying truth conditions, one may hope to explain all these variations by differences of complementation with respect to (a) the time or period for which the ability subsists, (b) the particular fully specified value of the action variables, and (c) the time relevant for the acting itself. Can itself is, in my own provisional opinion, a unitary semantical element. But those who have distinguished, e.g. a 'general' can from 'particular' can have performed an important service in forcing us to be clear about what exactly it is that a man could or could not have done. The (b)-place must be carefully and fully specified. The provision of two slots (a) and (c), for the times of the ability and the performance respectively, may seem questionable. But consider the fact that I may now, in Baker Street at 9.55 a.m., be able to catch the train from Paddington to Oxford at 10.15 a.m. Eight minutes later, however, at 10.03 a.m., if I have not progressed from Baker Street, then, given the state of the Inner Circle line and Marylebone Road, I shall certainly be unable to catch the train. What we have in this example is not a special case but a specially clear case. Both slots are always there — we cannot create them specially for the train case — but when they both take the same temporal specification (as they must in 'he could have done otherwise' in at least some important occurrences) then the ellipse of one of them is surely natural and intelligible enough. So much for the sentence he could have done otherwise as it figures in the dispute. The other urgent need is for a clarification of the determinism which the libertarian finds incompatible with his understanding of the sentence. II What determinism signifies J. L. Austin once maintained that determinism was 'the name of nothing clear'.8 But as a second-level non-scientific theory that the world admits of explanation by a certain kind of ground level scientific theory, it seems to me that the thesis can be made as plain as 'causality' and 'explanation' can. Whatever his other difficulties, I think the libertarian must find it depressingly easy to indicate what it is that he is afraid of. I propose to say that a scientific theory for a subject-matter s is deterministic if and only if the theory possesses a store of predicates and relation-words for the characterisation of s-items (events, situations), and affirms lawlike general statements L1, L2, . . . Ln, such that for every s-item sj it can find a description Dj, and s-item si with description Di which occurred some t seconds earlier, and a law L such that L implies (if a Di event occurs, then a Dj event occurs t seconds later).9 A deterministic theory is adequate if its vocabulary of descriptions D1, D2, . . . Dn and its laws L1, L2, . . . Ln together yield explanations which are of universal correct applicability and the statements L1, L2, . . . are true. As a first attempt then let us say that determinism is the theory that for every event (situation, state of the world or whatever) there is a true description Di and an adequate and deterministic theory T which explains that event under Di. I suppose our reason for thinking that this might hold is science's spectacular success in extending again and again the number and variety of events for which it can find theories with the title to be in my sense both adequate and deterministic. Someone may comment that it is hardly surprising that we have discovered the regularities which were there to be discovered; that our success shows nothing about the residue; nor does the possibility of such success really guarantee the operational or empirical intelligibility of the thesis of determinism. Perhaps it is not intelligible, it may be said. The charge ignores falsification however; and those who persist in subscribing to determinism (in spite of, e.g. quantum phenomena) surely might reply to the whole objection with this question: 'How big then is the residue? Can there really be, what the objection purports to achieve, an a priori estimation of it?' At this point, however, we stumble upon the widespread idea, presumably shared by the objector, that every situation must be infinitely describable. If it were, then getting evidence for determinism would certainly be like filling a broken pitcher. III The logical character of the incompatibility of determinism and the ability to do otherwise So much for serious determinism. It is a shaky hypothesis, and in its stricter forms open to disbelief It is not a thesis to be disarmed by a priori arguments against its truth or significance; and it is not obviously equivalent to the prima facie weaker thesis that every event has some cause. Its importance for freedom resides in the fact that if determinism is true and every action of every agent depends in its particular circumstances upon some specific physical condition being Satisfied, then actions cannot be torn free from the nexus of physical effects and fully determining causes.16 Here then we come to the problem of the incompatibility which the libertarian alleges between physical determinism and statements of the form 'he could at t' have done otherwise at t''.
IV Views of the self open to the libertarian It may be said that the whole preceding demonstration turns on a confusion between what lies in the agent and what lies outside him.20 It is perfectly absurd, it will be said, to lump together under conditions C things as diverse as the character of the agent, the present state of mind of the agent, the external causes of that state of mind, and the concrete particularities of the conditions under which he acts. It makes as much sense as saying that one of the circumstances under which an agent did a specific action was the circumstance that he was a man of a mean and murderous disposition. Nothing but confusion can come from such a way of speaking, it will be said; and the only possible philosophical outcome of speaking like this is a far fetched theory of the metaphysical, totally non-empirical, and characterless self whose difficulties match exactly the incoherences of the Lockean doctrine of substance - the thing with the property of having no properties, the substrate which explains the possibility of change by being both unchanged and identical with that which persists through change. Either the libertarian requires (cf. Section I (i)) that nothing in the world outside the free agent himself determine for that agent how he will change or deliberate to change the world, or the libertarian simply requires that determine for the agent how he will change or deliberate to change the world. It will then be said that if the requirement is stated in the former way we can and must distinguish what lies within the agent from what lies without. If the requirement is stated in the latter way, however, then even the agent himself is excluded from determining anything - even for himself - unless the self is outside the world altogether. This is an unintelligible conception. Finally it may be said that the libertarian's expression 'determining for the agent' is pure rhetoric - the man deliberates and thus determines for himself what change he will import. [See Locke - not the will that is free, the man is free.] I hope this states the objection as dissolutionists or compatibilists want to see it stated. But without the discovery of a specific mistake in the argument above, the absurdities of the metaphysical self cannot themselves suffice to disprove the inference from determinism to nobody can do otherwise than they do do. How exactly the metaphysical self could be supposed to compensate for physical determinism is not at all clear. But if determinism did really imply that if we were responsible then the doctrine of the metaphysical self would be true; and if the doctrine of the metaphysical self is absurd (as I for one am sure that it is), then either we are not responsible or the doctrine of determinism is not true. But then if determinism is true, the conclusion follows that we are not responsible. (At least in the sense of 'responsible' fixed by the question whether a man can do otherwise.) But that after all is exactly what the libertarian said. As for the confusion of character and circumstance, it is true that condition C groups them together. But why shouldn't it group them together without confusing them? Perhaps there is an important point to be made by comparing character and circumstance, by bringing out some similarity in them so far as historical inevitability is concerned. One can compare without confusing. In comparing for an important purpose one can also undermine the rationale of distinctions some people insist on making, if they are artificial or pointless distinctions. Maybe it is pointless to debate whether the sentence 'he could at t' have done otherwise at t'' does have the sense I have ascribed to it in the incompatibilist demonstration of Section III above until it has at least been shown that that sense is even a possible sense, or that it could do for the libertarian what he wanted. This is often taken to be equivalent to the following question: can the libertarian even specify a possible world, however different from the actual one, in which there are particular responsible actions which people can (in the libertarian's sense) do but do not do? Hume has been followed by a large number of philosophers in holding that not even a possible world of the required sort could be specified. If it were false that every event and every action were causally determined then the causally undetermined events and actions would surely, to that extent, be simply random. So the argument goes. That a man could have done x would mean no more than that it might have turned out that way - at random. It will be asked if it makes any better sense to hold a man responsible for actions which happen at random than for ones which arise from his character. Surely then, if it doesn't, we ought to prefer that our actions be caused? Considered simply as an argument this objection is circular, and flagrantly so. One cannot prove that determinism is a precondition of free will by an argument which employs as a premiss everything is either causally determined or random. This is nothing other than a form of the conclusion, that whatever is undetermined is random. This is what had to be shown. But in the form of a challenge something in the objection can stand. If an event is undetermined, if an event of different specification might have taken its place, then what does it mean to deny that the event is simply random? What is it justifiably to ascribe the action identical with the event or comprised of the event to an agent whom one holds responsible for that action? In the unclaimed ground between the properly or determinatically caused and the random, what is there in fact to be found? Some philosophers have ventured the idea that what would make the difference, within the field of physically undetermined events, between the random and the non-random is the presence or absence of a prior mental event such as a volition. It was in this tradition (which goes back at least as far as the clinamen or swerve of Epicurus and Lucretius) that Russell and Eddington tried to deploy the phenomena of quantum-indeterminacy as having a bearing upon the free-will issue.23
If - as seems likely - there is an uninterrupted chain of purely physical causation throughout the process from sense-organ to muscle, it follows that human actions are determined in the degree to which physics is deterministic. Now physics is only deterministic as regards macroscopic occurrences, and even in regard to them it asserts only very high probability, not certainty. It might be that, without infringing the laws of physics, intelligence could make improbable things happen, as Maxwell's demon would have defeated the second law of thermo-dynamics by opening the trapdoor to fast-moving particles and closing it to slow-moving ones. On these grounds it must be admitted that there is a bare possibility - not more - that, although occurrences in the brain do not infringe the laws of physics, nevertheless their outcome is not what it would be if no psychological factors were involved ... So for those who are anxious to assert the power of mind over matter it is possible to find a loophole. It may be maintained that one characteristic of living matter is a condition of unstable equilibrium, and that this condition is most highly developed in the brains of human beings. A rock weighing many tons might be so delicately poised on the summit of a conical mountain that a child could, by a gentle push, send it thundering down into any of the valleys below; here a tiny difference in the initial impulse makes an enormous difference to the result. Perhaps in the brain the unstable equilibrium is so delicate that the difference between two possible occurrences in one atom suffices to produce macroscopic differences in the movements of muscles. And since, according to quantum physics, there are no physical laws to determine which of several possible transitions a given atom will undergo, we may imagine that, in a brain, the choice between possible transitions is determined by a psychological cause called 'volition'. All this is possible, but no more than possible.Russell is not enthusiastic, and perhaps the idea is even less free of difficulty than he allows. (Could not the incidence of human acts of 'volition' upon quantum phenomena upset the probability distributions postulated by the quantum theory?) It is perplexing too that the theory bases action on occurrent mental events which it does not found in or relate to personality or character or even to purpose. Could it do this without seeming to threaten its own rationale in causal indeterminism? If the theory tried to find room for such components as these in the genesis of action, then would the whole idea of an as it were `immaterial realisation' of the agent, the source of the volitions -paradoxical and absurd as it already sounds - be defenceless against the suggestion that there was no criterion by which the self or spiritual nucleus of an agent would qualify as a non-bodily thing not accountable to or determined by neurophysiological and physical laws? Nor, for the same sort of reason, is it clear that Russell's suggestion can give any very clear account of what would justify comparing the role of a volition to that of the child who gives the stone a gentle push in one or other of several possible directions. But this is not the end of Eddington's and Russell's idea. They have simply given it a disastrously Cartesian expression. For indeterminism maybe all we really need to imagine or conceive is a world in which (a) there is some macroscopic indeterminacy founded in microscopic indeterminacy, and (b) an appreciable number of the free actions or policies or deliberations of individual agents, although they are not even in principle hypothetico-deductively derivable from antecedent conditions, can be such as to persuade us to fit them into meaningful sequences. We need not trace free actions back to volitions construed as little pushes aimed from outside the physical world. What we must find instead are patterns which are coherent and intelligible in the low level terms of practical deliberation, even though they are not amenable to the kind of generalisation or necessity which is the stuff of rigorous theory. On this conception the agent is conceived as an essentially and straightforwardly enmattered or embodied thing. His possible peculiarity as a natural thing among things in nature is that his biography unfolds not only non-deterministically but also intelligibly; non-deterministically in that personality and character are never something complete, and need not be the deterministic origin of action; intelligibly in that each new action or episode constitutes a comprehensible phase in the unfolding of the character, a further specification of what the man has by now become. For help with such ideas, in spite of the physicalistic form in which I have couched them, we look naturally in the direction of J.-P. Sartre, and would best look not at the crazily optimistic positions of the early plays Les Mouches or Huis Clos or of L'Etre et le Neant but to what he now soberly tries to make of his position.24 Here is Sartre's 1969 account of it.25
For the idea which I have never ceased to develop is that in the end one is always responsible for what is made of one. Even if one can do nothing else besides assume this responsibility. For I believe that a man can always make something out of what is made of him. This is the limit I would today accord to freedom: the small movement which makes of a totally conditioned social being someone who does not render back completely what his conditioning has given him. Which makes of Genet a poet when he had been rigorously conditioned to be a thief. Perhaps the book where I have best explained what I mean by freedom is in fact, Saint Genet. For Genet was made a thief, he said 'I am a thief', and this tiny change was the start of a process whereby he became a poet, and then eventually a being no longer even on the margin of society, someone who no longer knows where he is, who falls silent. It cannot be a happy freedom, in a case like this. Freedom is not a triumph. For Genet, it simply marked out certain routes which were not initially given.This is not of course the place to take up everything that is strange or interesting in the passage. Nor is the passage innocent of possible confusion where it employs the words rigorously conditioned, which belong with a view of the world which Sartre surely ought to see the life of Genet as refuting. But the capital point is that it may not matter if the world approximates to a world which satisfies the principles of a neurophysiological determinism provided only that this fails in the last resort to characterise the world completely, and provided that there are actions which, for all that they are causally under-determined, are answerable to practical reason, or are at least intelligible in that dimension. These are not random. V Conclusion: the prospects for a reasonable libertarianism The free-will dispute has reached a point where real progress depends not only on the deeper research into necessity, possibility, disposition and causality which logic and philosophy are now edging into position to achieve but also, I claim, upon a more precise and much more sympathetic examination of what the libertarian wants, of why he wants it, and of how his conception of metaphysical freedom is connected with political or social freedom. Whether or not it is our world - that is another question - we must continue to press the question, 'What is the possible world which would afford the autonomy of thought and agency the libertarian craves in this one?' (A) Can any possible world really afford us that long sought autonomy? And (B), if none can, then what must we do with all the feelings and arguments which have led so many philosophers and men to reject compatibilism? Nothing, I think, will make them oblige philosophy and without vestige or trace disappear. I shall end by outlining some further problems in the specification of the libertarian's world, and then try to indicate what I think it would signify if these problems were simply insurmountable. A. I have tried to describe an indeterministic world in which human beings rank as natural objects, as a set of natural objects amongst others, whose motions and capacities can nevertheless be appraised in a dimension defined by subtle and rather exacting standards of rationality. But in dropping the Cartesian conception of an extra-physical volitional origin of motion do I not exchange one mystery for another? How is it that just human beings, and other rational creatures if any, behave in the way they do, freely but practically rationally? Well, it might be said we have simply picked out the class of natural objects which do do so and we just happen ourselves to belong to it (which explains our interest in that category): to be puzzled about the question is like looking for some teleologically motivated agency which directed the course of evolution towards the emergence of some particular species and for its benefit wrote off countless others in the process - a search at once fruitless and prompted by a certain confinement of perspective, as if one were never allowed to see some thick and luxurious tree except from one angle in mid air just above it. (Compare the difficulty of believing that the earth is part of the Milky Way.) Again someone may ask, to what extent can a libertarian's 'developing or accumulating biography' view of persons and their characters supplant the cosmic unfairness of the determinist's view of these matters? If it is unfair to hold a man responsible for what through no fault of his own he is, is it not equally unfair to hold him responsible for his biography developing in one indeterministic fashion rather than another? If the reply were 'Well, it's him', would this do equally well for the compatibilist? Or wouldn't it? Is this simply to relapse into satisfaction with Hume's specious dilemma? When we confront these and other questions it may be said by some libertarians and others, we shall come to see quantum phenomena not as the missing clue, not as the one piece we need to complete our theory of free action, but as the anomaly which points to the need for a whole conceptual revolution in our way of thinking about causality - particularly in its connexion with generality, necessity and invariance.26 B. But let me now finish with something about the other possibility - that such a conceptual revolution is an incoherent fantasy, even though the answers to the queries I have put could only be discovered within one. Let us face the idea that in the last resort the questions raised by the libertarian's world of freedom cannot be answered either piecemeal or by some new perspective upon causality. What would this show? Not I think that the libertarian has failed to explicate the notion of freedom which we and he began with. What he began with may have been both correctly identified and, in the last analysis, incoherent. It was not obviously incoherent. It was conceivable that this freedom was conceivable. But, in the end, the freedom itself turned out to be not conceivable - unless perhaps as a limiting case (and an impossible one) of absence of various kinds of causal determination. What then? If we have the notion of freedom I have argued that we have, kept in place by he could have done otherwise understood in the sense I have ascribed to it; and if so understood this sentence may always be false and that notion is everywhere incoherent; then it can only darken counsel to pretend that our notion is another notion - some notion touted by utilitarians and dissolutionists, for instance - or to pretend that we never really had our deterministic notion. For all sorts of things in our social, judicial, and penal institutions, and all sorts of things in our relations with human beings, may be based (and are based I think) upon the supposition that men can do otherwise than they do do. Substitution of another notion of responsibility may be called for, but substitution is not the same as analysis. The practical and metaphysical import of substitution and analysis are completely different. If a dilemma exists here it should first be acknowledged and felt as such. Only barbarism and reaction can benefit by concealment. If the unreformed notion of responsibility, the notion which is our notion, is a sort of metaphysical joke must we not at the very least create some safe time or place in everyday life to laugh at it?27 A reformed notion of responsibility need not rest on the simple efficacy of punishment - which is by no means the same thing as the efficacity working through consciousness of moral norms or ideals28 - but it will not reconstruct what men at present feel by way of remorse at their own actions or by way of anger at those of others. Such looking backwards must be strictly senseless. Yet what happens if (except for instruction about the future) we try to ignore the past? What happens to moral consciousness itself as it arises from the generalisation of such affective attitudes? In a British Academy lecture P. F. Strawson29 once claimed that whatever we knew in favour of the hypothesis of total determinism, it could never be rational for us to opt out from all resentment or anger or gratitude or admiration or from the conceptual framework of responsibility in which these and like responses or attitudes have their meaning; no one who supposed that it would be rational had thought into what it would really signify for human life to attempt to abandon them. This was an important argument. Yet what it really told against, I think, was the utilitarian and substitutive resolution of the problem of freedom. It did not show the bankruptcy of libertarianism. How could a practical consideration - however all-embracing - prove the theoretical compatibility of freedom and determinism? But it does help the incompatibilist and the libertarian to improve his point about the range and variety of things which determinism puts in jeopardy, however 'panicky' or 'obscure' Strawson found libertarian metaphysics. What Strawson's lecture brings out is the character of the dilemma with which the problem of determinism confronts us - one set of considerations making an attitude rational, the other set undermining - that attitude - and the complex conceptual constitution of the notion of rationality which figures in the argument. The dilemma, whatever else it does, demonstrates the bewildering variety of heterogeneous and incommensurable considerations - truth, consistency, diversity of experience, comfort, security, fellow feeling - between which rationality has in real life to hold sway. The theme can scarcely find its natural development here, but perhaps it is the most distinctive of all the marks of rational man to have reasoned himself to a point where he falls into barbarism if he takes the notion of autonomous agency, whether mythical or not, either too seriously - or too lightly.