What changes our handwriting?
Each one of us has modified the copybook style in accordance with his individual character. Each one has unconsciously adopted a style of handwriting that is best suited to his tastes and inclinations and has consequently given to it a distinctive character.
Now, if handwriting bore no relationship to personality and was not influenced by the character of the individual, we would all be writing the beautiful Spencerian copperplate we were taught in our school days. But, as it is, not one in fifty thousand writes in this manner five years after leaving school.
Without pursuing the subject farther it must be evident to every thoughtful mind that handwriting does bear a very close and definite relationship to the personality of the writer. We see that everyone has a style of chirography peculiar to himself, and it is only reasonable to suppose that each feature of his writing reflects some personal trait or tendency; otherwise, why is there such a variety of features in handwritings? What would cause these various distinguishing characteristics of penmanship if it is not the individuality of the writers themselves?
Source: Graphology or How to Read Character from Handwriting BY SIMON ARKE American Institute of Graphology 305 Lenman Building Washington, D. C. 1903