JL Mackie – The Miracle of Theism (pages 110-115)

But in whichever of these ways we interpret his conclusion, Kant’s argument is open to criticism. The most glaring weakness is in the step from the proposition that ‘we ought to seek the highest good’ to the claim that it ‘must therefore be possible’. Even if, as Kant argues elsewhere, ‘ought’ implies ‘can’, the thesis that we ought to seek to promote the highest good implies only that we can seek to promote it, and perhaps,since rational seeking could not be completely fruitless, that we can to some extent actually promote it. But this does not require that the full realization of the highest good should be possible.

For example, it is thoroughly rational to try to improve the condition of human life, provided that some improvement is possible; there is no need to entertain vain hopes for its perfection. And even for the possibility of that full realization the most that would be needed is the possible existence of a wholly good and all-powerful governor of the world; the actual existence of such a governor would ensure not merely the possibility but the actuality of the highest good.

Kant might say that we can and should aspire to the ultimate realization of the highest good, and that a hope for such ultimate realization is necessarily involved in moral thought. But he cannot claim that even its possible realization is a necessary postulate of moral thought in general; it is not even a necessary postulate of that particular sort of moral theory which Kant himself developed. The willing of universal laws by and for all rational beings as such could be a strictly autonomous activity.

There are, indeed, recurrent tensions between Kant’s theism and his stress on the autonomy of morals. In sharp contrast with the popular view, and with Newman’s, Kant holds that neither our knowledge of God and of his will, nor that will itself, is the foundation of the moral law.

Yet because (as he thinks) we have to postulate a god who also wills these laws, as does every other free and rational will, he still calls them ‘commands of the Supreme Being’, but in a sense which is only a pale shadow of what is intended by most theological moralists. Again, Kant holds that no ‘desired results’ are ‘the proper motive of obedience’ to these laws, indeed that fear of punishment or hope of reward ‘if taken as principles,would destroy the whole moral worth of actions’. Yet his belief that there is something appropriate about the proportioning of happiness to morality — a retributive thesis — again seems to be a pale shadow of the popular reliance on punishments and rewards. Is not this true also of his stress (after all) on happiness,whose conjunction with virtue we are to take not merely as a legitimate hope but as a postulate of moral thought? Would not a thorough going recognition of the autonomy of morals lead rather to the Stoic view that morality needs no actual happiness beyond the consciousness of right action itself?

Kant himself seems to have been aware of these difficulties, and a passage in his Metaphysic of Morals suggests a quite different proof of God’s existence: again a moral proof, but one which anticipates Newman’s argument about conscience.

Now this original intellectual and . . . moral capacity, called conscience,has this peculiarity in it, that although its business is a business of manwith himself, yet he finds himself compelled by his reason to transact itas if at the command of another person . . . in all duties the conscienceof the man must regard another than himself as the judge of his actions. . . Now this other may be an actual or a merely ideal person which reason frames to itself. Such an idealized person. . . . must be one who knows the heart . . . at the same time he must also be all-obliging, that is, must be or be conceived as a person in respect of whom all duties are to be regarded as his commands . . . Now since such a moral being must at the same time possess all power (in heaven and earth), since otherwise he could not give his commands their proper effect, and since such a moral being possessing power over all is called God, hence conscience must be conceived as the subjective principle of a responsibility for one’s deeds before God, nay, this latter concept i scontained (though it be only obscurely) in every moral self-consciousness. (293-4)

Here Kant is vacillating between the recognition of the merely psychological phenomenon of the setting up of an ideal spectator ( Adam Smith’s ‘man within the breast ‘4) and the suggestion that moral thought has at least to postulate the real existence of an outside authority but how weak a reason he offers for the ascription of all power to this moral being! In any case, in so far as this argument anticipates Newman’s, it is open to the same criticisms.

We need not labour these internal tensions and vacillations. What is important is that even if moral thought is as Kant describes it, it does not follow that such thought has even to postulate the existence of a god, let alone that we can infer the real existence of a god from the character of that thought.

Sidgwick: the Duality of Practical Reason

Another variant of the moral argument is clearly stated, but not endorsed, by Sidgwick.5 This starts from ‘the duality of practical reason’, the fact that both prudential egoism and the commands of conscience are practically reasonable, each without qualification, and yet that, if there is neither a god nor anything like a god,they will not always coincide. Its premiseses are:

1. What I have most reason to do is always what will best secure my own happiness in the long run.
2. What I have most reason to do is always what morality requires.
3. If there is no moral government of the universe, what will best secure my own happiness is not always what morality requires.

The first two of these premisses would indeed entail that prudence and morality always coincide; for if they required different choices in the same situation, it could not be true that each of these different choices was the one that I had most reason to make: that is, these premisses could not both be true. But then, if prudence and morality will always coincide only if there is a moral government of the universe, it follows that there must be such a government, that is, either a god or something like a god.

This argument is plainly valid, though its conclusion is not quite what traditional theism asserts: moral government would not need to include a personal god. But are the premisses true? Sidgwick, for one, regarded the first two as inescapable intuitions about what is reasonable in conduct–taking the second as prescribing social duty in a utilitarian sense. Also, if there is no moral government of the universe, then presumably the present life is all we have to take into account; and it is an easily established empirical truth that in this life the demands of utilitarian morality–the promotion of the general happiness–do not always coincide with what will best promote one’s own happiness. This, then, establishes the third premiss.

But although Sidgwick, for these reasons, accepted all three premisses, he did not accept the conclusion. He preferred to admit that there is a fundamental and unresolved chaos in our practical reasoning, and that the human intellect cannot frame a fully satisfactory ideal of rational conduct: ‘the mere fact that I cannot act rationally without assuming a certain proposition, does not appear to me,–as it does to some minds,–a sufficient ground for believing it to be true’. Equally he rejects what he calls ‘the Kantian resource of thinking myself under a moral necessity to regard all my duties as if they were commandments of God, although not entitled to hold speculatively that any such Supreme Being exists “as Real”‘. (In this reference to ‘the Kantian resource’, Sidgwick is clearly favouring the second of the two interpretations of Kant offered above; but the previous comment on whatappears ‘to some minds’ would apply to the first.) Sidgwick adds: ‘I am so far from feeling bound to believe for purposes of practice what I see no ground for holding as a speculative truth, that I cannot even conceive the state of mind which these words seem to describe, except as a momentary half- wilful irrationality, committed in a violent access of philosophic despair’.

Is Sidgwick perverse in refusing to accept this conclusion? I think not. It is rather that he has put his finger on the basic weakness of almost every form of moral argument for the existence of a god. A set of beliefs, even if they are called ‘intuitions’, about how one ought to act cannot be a good reason for settling a factual issue, a way of determining what is the case, or even for deciding what to ‘believe for practical purposes’. Practical choices must be based on factual beliefs,not the other way round, though beliefs alone, of course, will not determine choices.
To see this, let us take an analogous case. Most of those who have discussed imperative logic have assumed that such syllogisms as this are valid: ‘Eat no animal fats; butter is an animal fat; so don’t eat butter’. But if that syllogism is valid, so must this one be: ‘Eat no animal fats; you may eat butter; so butter is not an animal fat’. That is, there can be a valid syllogism with one imperative and one permissive premiss, and this would still be valid if the permissive premiss were strengthened to an imperative–in our example, to ‘Eat butter’. But such a pair of imperative premisses (or an imperative along with a permissive one) could not objectively establish the truth of the factual conclusion. They show only that anyone who coherently issues both imperatives (or the imperative and the permission) must believe the conclusion to be true. Again, what should we say about a general who accepted these three premisses:

1. If the enemy are advancing in overwhelming strength, then, if we do not withdraw, our army will be wiped out;
2. We must not allow our army to be wiped out;
3. We must not withdraw, because that would mean letting down our allies;
   and concluded, on these grounds alone, that the enemy were not advancing in overwhelming strength?

In all such cases, what it is rational to do depends upon what the facts are; but we cannot take what we are inclined to think that it is rational to do as evidence about those facts. To use a conjunction of practical judgements to try to establish what the facts are would be to put the cart before the horse. We must rely on speculative reasoning first to determine what is the case, and then frame our practical and moral beliefs and attitudes in the light of these facts. There is a direction of supervenience: since what is morally and practically rational supervenes upon what is the case, what it is rational to believe with a view to practice, or to choose to do,must similarly supervene upon what it is rational to believe about what is the case.

But this is what Kant was denying when, as we saw, he maintained the primacy ofpure practical reason. He refers, indeed, to Thomas Wizenmann, who had brought what is essentially our objection, or Sidgwick’s, against his argument. Kant concedes that we cannot argue from a want founded merely on inclination to the reality of its object or of what is needed to satisfy it, but he thinks it is otherwise when we have ‘a want of reason springing from an objective determining principle of the will, namely the moral law’. Since it is a duty to realize the summum bonum to the utmost of ourpower, it must be possible, and ‘consequently it is unavoidable for every rational being . . . to assume what is necessary for its objective possibility. The assumption is as necessary as the moral law, in connection with which alone it is valid’ (289,note). Kant admits that where practical reason ‘merely regulat[es] the inclinations under the sensible principle of happiness, we could not require speculative reason to take its principles from such a source’. This, he sees, would lead to absurd fantasies. But he thinks that pure practical reason, which determines the moral law,is in a different position.

‘But if pure reason of itself can be practical and is actually so, as the consciousness of the moral law proves, then it is still only one and the same reason which, whether in a theoretical or a practical point of view, judges according to a priori principles . . .’ Propositions established in this way, he holds, ‘are not additions to its[i.e. reason’s] insight, but yet are extensions of its employment in another, namely a practical, aspect . . .’ ‘Nor’, he says, ‘could we reverse the order, and require pure practical reason to be subordinate to the speculative, since all interest is ultimately practical, and even that of speculative reason is conditional, and it is only in the practical employment that it is complete.’ (261-2)

However, what this last remark can mean is unclear, and the reply to Wizenmann merely repeats the original argument. Nothing has been done to explain how pure practical reason could escape the constraints which, as Kant admits, apply to practical reason in general. If a certain practical principle presupposes certain factual propositions, then reason, however pure, cannot establish the validity of that practical principle without independently showing that those factual propositions are true. We cannot therefore use the practical principle to prove that these are truths of fact. This consideration is fatal to Kant argument in the Critique ofPractical Reason, just as it is to the argument which Sidgwick formulated, but rejected precisely on this account.
Whether there are other ways of resolving Sidgwick’s paradox is not our present concern. It may be that his first two premisses do not hold without qualification as principles of practical rationality. But if all such escape routes were blocked, the right conclusion to draw would be the one that Sidgwick himself drew, that there is no fully coherent ideal of practical reason.