be ‘good’ means to possess the property in question. Such theories I call ‘Naturalistic.’ I have thus appropriated the name Naturalism to a particular method of approaching Ethics—a method which, strictly understood, is inconsistent with the possibility of any Ethics whatsoever. This method consists in substituting for ‘good’ some one property of a natural object or of a collection of natural objects; and in thus replacing Ethics by some one of the natural sciences. In general the science thus substituted is one of the sciences specially concerned with man, owing to the general mistake (for such I hold it to be) of regarding the matter of Ethics as confined to human conduct. In general, Psychology has been the science substituted, as by J.S. Mill; or Sociology, as by Professor Clifford, and other modern writers. But any other science might equally well be substituted. It is the same fallacy which is implied, when Professor Tyndall recommends us to ‘conform to the laws of matter’: and here the science which is proposed to substitute for Ethics is simply Physics. The name then is perfectly general; for, no matter what the something is that good is held to mean, the theory is still Naturalism. Whether good be defined as yellow or green or blue, as loud or soft, as round or square, as sweet or bitter, as productive of life or productive of pleasure, as willed or desired or felt: whichever of these or of any other object in the world, good may be held to mean, the theory, which holds it to mean them, will be a naturalistic theory. I have called such theories naturalistic because all of these terms denote properties, simple or complex, of some simple or complex natural object; and, before I proceed to consider them, it will be well to define what is meant by ‘nature’ and by ‘natural objects.’
By ‘nature,’ then, I do mean and have meant that which is the subject-matter of the natural sciences and also of psychology. It may be said to include all that has existed, does exist, or will exist in time. If we consider whether any object is of such a nature that it may be said to exist now, to have existed, or to be about to exist, then we may know that that object is a natural object, and that nothing, of which this is not true, is a natural object. Thus, for instance, of our minds we should say that they did exist yesterday, that they do exist to-day, and
