a natural product. But that is not what is meant by this phrase; nature is again used to mean a mere part of nature; only this time the part meant is not so much the normal as an arbitrary minimum of what is necessary for life. And when this minimum is recommended as “natural”—as the way of life to which Nature points her finger—then the naturalistic fallacy is used. Against this position I wish only to point out that though the performance of certain acts, not in themselves desirable, may be
excused as necessary means to the preservation of life, that is no reason for
praising them, or advising us to limit ourselves to those simple actions which are necessary, if it is possible for us to improve our condition even at the expense of doing what is in this sense unnecessary. Nature does indeed set limits to what is possible; she does control the means we have at our disposal for obtaining what is good; and of this fact, practical Ethics, as we shall see later, must certainly take account: but when she is supposed to have a preference for what is necessary, what is necessary means only what is necessary to obtain a certain end, presupposed as the highest good; and what the highest good is Nature cannot determine. Why should we suppose that what is merely necessary to life is ipso facto better than what is necessary to the study of metaphysics, useless as that study may appear? It may be that life is only worth living, because it enables us to study metaphysics—is a necessary means thereto. The fallacy of this argument from nature has been discovered as long ago as Lucian. “I was almost inclined to laugh,” says Callicratidas, in one of the dialogues imputed to him,
4 “just now, when Charicles was praising irrational brutes and the savagery of the Scythians: in the heat of his argument he was almost repenting that he was born a Greek. What wonder if lions and bears and pigs do not act as I was proposing? That which reasoning would fairly lead a man to choose, cannot be had by creatures that do not reason, simply because they are so stupid. If Prometheus or some other god had given each of them the intelligence of a man, then they would not have lived in deserts and mountains nor fed on one another. They would have built temples just as we do, each would have lived in the centre of his family, and they would have formed a nation bound by mutual laws. Is it anything surprising that brutes, who have had the misfortune to be unable to obtain by forethought any of the goods, with which reasoning provides us, should have missed love too? Lions do not love; but neither do they philosophise; bears do not love; but the reason is they do not know the sweets of friendship. It is only men, who, by their wisdom and their knowledge, after many trials, have chosen what is best.”
29. To argue that a thing is good because it is “natural,” or bad because it is “unnatural,” in these common senses of the term, is therefore certainly fallacious: and yet such arguments are very frequently used. But they do not commonly pretend to give a systematic theory of Ethics. Among attempts to systematise an appeal to nature, that which is now most prevalent is to be found in the application to ethical questions of the term “Evolution”—in the ethical doctrines which have been called “Evolutionistic.” These doctrines are those which maintain that the course of “evolution,” while it shows us the direction in which we are developing, thereby and for that reason shows us the direction in which we ought to develop. Writers, who maintain such a doctrine, are at present very numerous and very popular; and I propose to take as my example the writer, who is perhaps the best known of them all—Mr. Herbert Spencer. Mr. Spencer’s doctrine, it must be owned, does not offer the clearest example of the naturalistic fallacy as used in support of Evolutionistic Ethics. A clearer example might be found in the doctrine of Guyau,5 a writer who has lately had considerable vogue in France, but who is not so well known as Spencer. Guyau might almost be called a disciple of Spencer; he is frankly evolutionistic, and frankly naturalistic; and I may mention that he does not seem to think that he differs from Spencer by reason of his naturalism. The point in which he has criticised Spencer concerns the question how far the ends of “pleasure” and of “increased life” coincide as motives and means to the attainment of the ideal: he does not seem to think that he differs from Spencer in the fundamental principle that the ideal is “Quantity of life, measured in breadth as well as in length,” or, as Guyau says, “Expansion and intensity of life”; nor in the naturalistic reason which he gives for this principle. And I am not sure that he does differ from Spencer in these points. Spencer does, as I shall show, use the naturalistic fallacy in details; but with regard to his fundamental principles, the following doubts occur: Is he fundamentally a Hedonist? And, if so, is he a naturalistic Hedonist? In that case he would better have been treated in my next chapter. Does he hold that a tendency to increase quantity of life is merely a criterion of good conduct? Or does he hold that such increase of life is marked out by nature as an end at which we ought to aim?
I think his language in various places would give colour to all these hypotheses; though some of them are mutually inconsistent. I will try to discuss the main points.
30. The modern vogue of “Evolution” is chiefly owing to Darwin’s investigations as to the origin of species. Darwin formed
