Identity, Law of. This is a name given to the axiom that everything is
what it is. A = A. It has for its correlative the Law of
that the same proposition and its contradictory cannot both be true.
Both positions may seem to the beginner mere truisms, and the assertion
of them to be no better than trifling. The results of logic, however,
follow from them; in fact they lie at the foundation of all reasoning
Identity, Personal. Our being each of us one and the same person in
spite of the various changes that pass on us through life. The validity
of arguments in defence of this may be disputed, but no man can shake
off the conviction that it is so. Our personal identity has its root in
the ego. Far back as the time may be, and changed as I may be in aspect,
from capacities and habitual feelings, I know that it was I who said the
word or did the deed which I remember.
The most valuable English treatise on Personal Identity is one by Bishop
Butler, appended to the Analogy.