although its exterior linguistic form is that of a command or a wish. But he can, of course, give it a meaning. If I ask him, ‘What do you mean by “three times as blue”?’, he can arbitrarily indicate certain definite physical circumstances concerning the serenity of the sky which he wants his phrase to be the description of. And then, perhaps, I shall be able to follow his directions; his wish will have become meaningful for me.
Thus, whenever we ask about a sentence, ‘What does it mean?’, what we expect is instruction as to the circumstances in which the sentence is to be used; we want a description of the conditions under which the sentence will form a true proposition, and of those which will make it false. The meaning of a word or a combination of words is, in this way, determined by a set of rules which regulate their use and which, following Wittgenstein, we may call the rules of their grammar, taking this word in its widest sense.
(If the preceding remarks about meaning are as correct as I am convinced they are, this will, to a large measure, be due to conversations with Wittgenstein which have greatly influenced my own views about these matters. I can hardly exaggerate my indebtedness to this philosopher. I do not wish to impute to him any responsibility for the contents of this article, but I have reason to hope that he will agree with the main substance of it.)
Stating the meaning of a sentence amounts to stating the rules according to which the sentence is to be used, and this is the same as stating the way in which it can be verified (or falsified). The meaning of a proposition is the method of its verification.
The ‘grammatical’ rules will partly consist of ordinary definitions, i.e., explanations of words by means of other words, partly of what are called ‘ostensive’ definitions, i.e., explanations by means of a procedure which puts the words to actual use. The simplest form of an ostensive definition is a pointing gesture combined with the pronouncing of the word, as when we teach a child the signification of the sound ‘blue’ by showing a blue object. But in most cases the ostensive definition is of a more complicated form; we cannot point to an object corresponding to words like ‘because’, ‘immediate’, ‘chance’, ‘again’, etc. In these cases we require the presence of certain complex situations, and the meaning of the words is defined by the way we use them in these different situations.
