In the first chapter we have noticed the opinion that identities are fundamental to all logic. We will now consider some other views of the value of identities.

Identities are frequently used in common life by people who seem to imagine that they can draw important conclusions respecting conduct or matters of fact from them. I have heard of a man who gained the double reputation of being a philosopher and a fatalist by the repeated enunciation of the identity “Whatever will be, will be”; and the Italian equivalent of this makes up an appreciable part of one of Mr. Robert Hichens’ novels. Further, the identity “Life is Life” has not only been often accepted as an explanation for a particular way of living but has even been considered by an authoress who calls herself “Zack” to be an appropriate title for a novel; while “Business is Business” is frequently thought to provide an excuse for dishonesty in trading, for which purpose it is plainly inadequate.

Another example is given by a poem of Mr. Kipling, where he seems to assert that “East is East” and “West is West” imply that “never the twain shall meet.” The conclusion, now, is false; for, since the world is round—as geography books still maintain by arguments which strike every intelligent child as invalid[20]—what is called the “West” does, in fact, merge into the “East.” Even if we are to take the statement metaphorically, it is still untrue, as the Japanese nation has shown.

The law-courts are often rightly blamed for being strenuous opponents of the spread of modern logic: the frequent misuse of and, or, the, and provided that in them is notorious. But the fault seems partly to lie in the uncomplicated nature of the logical problems which are dealt with in them. Thus it is no uncommon thing for somebody to appear there who is unable to establish his own identity, or for A to assert that B was “not himself” when he made a will leaving his money to C.

The chief use of identities is in implication. Since, in logic, we so understand implication[21] that any true proposition implies and is implied by any other true proposition; if one is convinced of the truth of the proposition Q, it is advisable to choose one or more identities P, whose truth is undoubted, and say that P implies Q. Thus, Mr. Austen Chamberlain, according to The Times of March 27, 1909, professed to deduce the conclusion that it is not right that women should have votes from the premisses that “man is man” and “woman is woman.” This method requires that one should have made up one’s mind about the conclusion before discovering the premisses—by what, no doubt, Jevons would call an “inverse or inductive method.” Thus the method is of use only in speeches and in giving good advice.

Mr. Austen Chamberlain afterwards rather destroyed one’s belief in the truth of his premisses by putting limits to the validity of the principle of identity. In the course of the Debate on the Budget of 1909, he maintained, against Mr. Lloyd George, that a joke was a joke except when it was an untruth: Mr. Lloyd George, apparently, being of the plausible opinion that a joke is a joke under all circumstances.

CHAPTER IV