IDENTITY
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.
FOOTNOTES:
[20] The argument about the hull of a ship disappearing first is not
convincing, since it would equally well prove that the surface of the
earth was, for example, corrugated on a large scale. If the common-sense
of the reader were supposed to dismiss the possibility of water clinging
to such corrugations, it might equally be supposed to dismiss the
possibility of water clinging to a spherical earth. Traditional
geography books, no doubt, gave rise to the opinions held by Lady Blount
and the Zetetic Society.
[21] The subject of Implication will be further considered in Chapter
XIX.