Page:Principia Ethica 1922.djvu/43

Rh be writing on Ethics, for my main object is to help towards discovering that definition. It is just because I think there will be less risk of error in our search for a definition of ‘the good,’ that I am now insisting that good is indefinable. I must try to explain the difference between these two. I suppose it may be granted that ‘good’ is an adjective. Well, ‘the good,’ ‘that which is good,’ must therefore be the substantive to which the adjective ‘good’ will apply: it must be the whole of that to which the adjective will apply, and the adjective must always truly apply to it. But if it is that to which the adjective will apply, it must be something different from that adjective itself; and the whole of that something different, whatever it is, will be our definition of the good. Now it may be that this something will have other adjectives, beside ‘good,’ that will apply to it. It may be full of pleasure, for example; it may be intelligent: and if those two adjectives are really part of its definition, then it will certainly be true, that pleasure and intelligence are good. And many people appear to think that, if we say ‘Pleasure and intelligence are good,’ or if we say ‘Only pleasure and intelligence are good,’ we are defining ‘good.’ Well, I cannot deny that propositions of this nature may sometimes be called definitions; I do not know well enough how the word is generally used to decide upon this point. I only wish it to be understood that that is not what I mean when I say there is no possible definition of good, and that I shall not mean this if I use the word again. I do most fully believe that some true proposition of the form ‘Intelligence is good and intelligence alone is good’ can be found; if none could be found, our definition of the good would be impossible. As it is, I believe the good to be definable; and yet I still say that good itself is indefinable.

10. ‘Good,’ then, if we mean by it that quality which we assert to belong to a thing, when we say that the thing is good, is incapable of any definition, in the most important sense of that word. The most important sense of ‘definition’ is that in which a definition states what are the parts which invariably compose a certain whole; and in this sense ‘good’ has no definition because it is simple and has no parts. It is one of