looking for an "easy mark." Plain signatures of the character noted
above are not the ones usually selected by forgers for simulation.
Forgers are always hunting for the illegible as in it they can best
hide their identity.

It is said to be an utter impossibility for one person to imitate
successfully a page of writing of another. The person attempting the
forgery should be able to accomplish the following: First, he must
know all the characteristics of his own hand; second, he must be able
to kill all the characteristics of his own hand; third, he must know
all of the characteristics in the hand he is imitating; fourth, he
must be able to assume characteristics of the other's hand at will.
These four points are insuperable obstacles, and the forger does not
live who has surmounted or can surmount them.

To understand the principles on which an expert in handwriting bases
his work, consider for a moment how a person's style of writing is
developed. He begins by copying the forms set for him by a teacher. He
approximates more or less closely to these forms. His handwriting is
set, formal, and without character. As soon as he leaves off following
the copy book, however, his writing begins to take on individual
characteristics. These are for the most part unconscious. He thinks of
what he is writing, not how. In time these peculiarities, which creep
gradually into a man's writing, become fixed habits. By the time he
is, say, twenty-five years old, his writing is settled. After that it
may vary, may grow better or worse, but is certain to retain those
distinguishing marks which, in the man himself, we call personality.
This personality remains. He cannot disguise it, except in a
superficial way, any more than he can change his own character.