The Pursuit of Certainty. Shirley Robin Letwin

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СКАЧАТЬ man was brutish but because animals were no less spiritual than he. At times Hume almost paraphrased Montaigne to argue that insofar as men reasoned, animals did too. It had long been observed, he said, that animals behaved very much as men did, and that they adapted means to ends in the same manner. It was only natural to assume that the causes of similar behaviour were similar:

      We are conscious that we ourselves in adapting means to ends are guided by reason¹ and design, and that ’tis not ignorantly nor casually we perform those actions, which tend to self-preservation, to the obtaining pleasure and avoiding pain. When therefore we see other creatures, in millions of instances perform like actions, and direct them to like ends, all our principles of reason and probability carry us with an invincible force to believe the existence of a like cause. … The resemblance betwixt the actions of animals and those of men is so entire in this respect, that the very first action of the first animal we shall please to pitch on, will afford us an incontestable argument for the present doctrine.²

      Hume pointed out that this was not just a parenthetical observation but at the heart of his argument—“This doctrine is as useful as it is obvious, and furnishes us with a kind of touchstone, by which we may try every system in this species of philosophy.”³ It is easy, he declared, to test any hypothesis advanced to explain a mental operation by asking whether it applies equally well to men and beasts. Other philosophical systems supposed “a subtilty and refinement of thought” in a degree that exceeded the capacities not only of animals but also of most human beings. His own system, however, could “equally account for the reasonings of beasts as well as for those of the human species.” And it was the only philosophical system that could. Since it is generally admitted that beasts do not perceive any real connection among objects, or form any general conclusions, yet learn from experience and adapt their behaviour accordingly, it is evident that “rational” behaviour does not depend on reason in the sense given it by philosophers: “I assert they [rational actions of animals] proceed from a reasoning, that is not in itself different, nor founded on different principles from that which appears in human nature.”¹

      Here perhaps Hume was more artful than candid. The force of his argument about animals is certainly that if we do not need to postulate a creative reason in order to explain the behaviour of animals, we need not do so for humans. But he avoided making an offensive statement by reversing the order, and declaring that, “All this was sufficiently evident with respect to man. But with respect to beasts there cannot be the least suspicion of mistake; which must be own’d to be a strong confirmation, or rather an invincible proof of my system.”² Hume was tactful, but his meaning is clear. Was it not odd, he asked, that men took their own reason for granted, but were astonished by the instinct of animals? It was only because they had not been able to reduce animal instinct to the same principles. In the light of his new philosophy, however, the problem vanished, because it removed the apparent distinction between human reason and animal instinct. It discovered reason to be “nothing but a wonderful and unintelligible instinct in our souls which carries us along a certain train of ideas, and endows them with particular qualities, according to their particular situations and relations.” It was an instinct that resulted from habit, and “habit is nothing but one of the principles of nature and derives all its force from that origin.”³ Man, then, was not outside or beyond nature, but part of it, merely a more elaborate animal: “Everything is conducted by springs and principles, which are not peculiar to man, or any species of animals.”⁴ Montaigne’s essays had been given a metaphysical foundation.

      That Hume had done something radical, all his contemporaries sensed. What the radicalism consisted in, however, they did not quite grasp. Only Kant recognized the full implications of Hume’s theory. He saw the import of Hume’s concentration on the “necessity” of the causal relation, that he had denied not the reality of causation or the necessity of reasoning in the ordinary way, but rather the existence of “pure reason.” As Hume had reduced reason to nature, Kant hoped to save reason by divorcing it from nature more thoroughly than anyone had yet dared. He purified reason of its traditional character as pupil, receiving what nature chose to give, and transformed it into a judge, “who compels the witnesses to reply to those questions which he himself thinks fit to propose.”¹ Thus Kant put the defence of creative reason on a totally new footing, which was, he hoped, not so vulnerable as Hume had shown the old one to be.

      If one accepted Hume’s picture of human nature, the whole hierarchy of being was rearranged. The Treatise proposed a metaphysics that was profoundly subversive of the Christian outlook. It was no wonder that Hume’s friends wished him to withhold from publication his Dialogue on Natural Religion, and that he should have taken such great pains to insure its appearance after his death. For the Dialogue stated the postulate upon which the Treatise was based in its most general and simple form.

      The general question of how mind and matter were related had interested Hume from the beginning. He had studied Bayle’s account of Strato’s atheism and Cicero’s Dialogue of the Nature of the Gods, and was curious about the Cartesian philosophy of the brain. He had noticed throughout the history of philosophy that the most prevalent views had driven a sharp line between matter and spirit. Either they took up an atomistic, materialist position, like that of Epicurus, Democritus, Leucippus, and asserted that there was nothing but senseless matter and chance, or else they insisted that nature could not be explained without adding a spiritual, ordering force beyond matter. There was, however, a third possibility, suggested by Strato, and discussed by Cicero, that order is somehow inherent in matter. Strato’s atheism was “the most dangerous of the ancient, holding the origin of the world from nature or a matter endowed with activity,” Hume remarked in his notes.² What he himself had decided, he made plain in the Dialogues Concerning Natural Religion.

      Thought is not the only principle of order disclosed in experience, he pointed out. There are an infinite number of springs and principles which even our limited knowledge of nature shows her to possess—heat and cold, attraction and repulsion, instinct and generation. We know that every part of nature has its own life and motion, which not only operates it, but coordinates it with the whole. Our experience would seem to deny the possibility of matter utterly devoid of order, or, even spirit without matter. Certainly in all instances that we know, thought can influence matter only when it is joined to it, and it can be as easily influenced by matter. We have no reason to make “this little agitation of the brain” the model of the universe.³

      Besides, as we constantly see reason arise from generation, never generation from reason, we might more easily make generation the principle of order than reason. It is no less intelligible or compatible with experience to say that the world arose by vegetation from a seed, than to say that it arose from a divine reason or contrivance.¹ An orderly system might as easily have been spun from the belly of an infinite spider as from a mind. Reason itself is no more intelligible than any other ordering principle: “But reason, in its internal fabric and structure, is really as little known to us as instinct or vegetation; and perhaps even that vague, undeterminate word, nature, to which the vulgar refer everything is not at bottom more inexplicable.”²

      In the Dialogue, no one of the disputants gains a victory, although no one really refutes Philo’s statement:

      For aught we can know a priori, matter may contain the source or spring of order originally within itself, as well as mind does; and there is no more difficulty in conceiving, that the several elements from an internal unknown cause, may fall into the most exquisite arrangement, than to conceive that their ideas, in the great universal mind, from a like internal unknown cause, fall into that arrangement. The equal possibility of both these suppositions is allowed.³

      The emphasis falls not so much on any particular theory, as on denying the possibility of knowing what either matter or mind is, or precisely how the universe is arranged: “These words, generation, reason, mark only certain powers and energies in nature, whose effects are known but whose essence is incomprehensible; СКАЧАТЬ