According to graphologists, handwriting, like voice, constitution, and movements of facial muscles, is an individual feature of a person. Just as there are no two identical people, so there cannot be two absolutely identical handwritings.
The French abbot Jean-Hippolyte Michonne began to seriously study this issue in the 19th century. He collected and systematized a huge number of samples and, having analyzed them, put forward his theory about the correspondence of certain peculiarities of writing letters with traits of a person's character. Since that time, graphology as a science began to be studied everywhere. Aspects for a detailed study were: size, slope, width, pressure, writing features, the distance between letters and words. Further work consisted in generalizing all these data in order to determine the characteristics of the character and psychological state of a person.
At the beginning of the 20th century, Germany became the center of graphological research. The German physiologist Wilhelm Preyer, using the example of his patients who lost both hands, found that with the help of a pen clamped by their teeth or toes, they write in approximately the same way as if they were doing it with their hand. Therefore, he concluded that the handwriting of the hand is the handwriting of the brain, determined by psychomotor energy. Nowadays, graphology helps doctors, psychologists and even forensic scientists in many ways.