The following proposition seems to me in a high degree probable—namely, that any animal whatever, endowed with well-marked social instincts (5. Sir B. Brodie, after observing that man is a social animal (‘Psychological Enquiries,’ 1854, p. 192), asks the pregnant question, “ought not this to settle the disputed question as to the existence of a moral sense?” Similar ideas have probably occurred to many persons, as they did long ago to Marcus Aurelius. Mr. J.S. Mill speaks, in his celebrated work, ‘Utilitarianism,’ (1864, pp. 45, 46), of the social feelings as a “powerful natural sentiment,” and as “the natural basis of sentiment for utilitarian morality.” Again he says, “Like the other acquired capacities above referred to, the moral faculty, if not a part of our nature, is a natural out-growth from it; capable, like them, in a certain small degree of springing up spontaneously.” But in opposition to all this, he also remarks, “if, as in my own belief, the moral feelings are not innate, but acquired, they are not for that reason less natural.” It is with hesitation that I venture to differ at all from so profound a thinker, but it can hardly be disputed that the social feelings are instinctive or innate in the lower animals; and why should they not be so in man? Mr. Bain (see, for instance, ‘The Emotions and the Will,’ 1865, p. 481) and others believe that the moral sense is acquired by each individual during his lifetime. On the general theory of evolution this is at least extremely improbable. The ignoring of all transmitted mental qualities will, as it seems to me, be hereafter judged as a most serious blemish in the works of Mr. Mill.), the parental and filial affections being here included, would inevitably acquire a moral sense or conscience, as soon as its intellectual powers had become as well, or nearly as well developed, as in man. For, FIRSTLY, the social instincts lead an animal to take pleasure in the society of its fellows, to feel a certain amount of sympathy with them, and to perform various services for them. The services may be of a definite and evidently instinctive nature; or there may be only a wish and readiness, as with most of the higher social animals, to aid their fellows in certain general ways. But these feelings and services are by no means extended to all the individuals of the same species, only to those of the same association. SECONDLY, as soon as the mental faculties had become highly developed, images of all past actions and motives would be incessantly passing through the brain of each individual: and that feeling of dissatisfaction, or even misery, which invariably results, as we shall hereafter see, from any unsatisfied instinct, would arise, as often as it was perceived that the enduring and always present social instinct had yielded to some other instinct, at the time stronger, but neither enduring in its nature, nor leaving behind it a very vivid impression. It is clear that