In contemporary society onanism is probably the most frequent sexual act. I think individualization goes hand in hand with onanism (no pun intended). The more people are thrown back on themselves and the more space they have for themselves, the higher the chances are they will sexually pleasure themselves.
The universality of the phenomenon leads to a wealth of expressions: next to masturbation, manustrupation, onanism, self-abuse, self-pollution, auto- or monosexual are the more popular ones like tossing off, jerking off, beating off, getting off, cumming, spanking the monkey, shooting. Decent descriptions are numerous: playing with yourself, pleasuring yourself, coming by yourself...
In the eighteenth century entire disertations appeared about onanism and its dangers. In 1758 the enlightened doctor S.A.D. Tissot devoted a learned disquisition in Latin to the subject, which in 1760 was translated in French and after that appeared in dozens of prints and translations.
His theory was clear and simple. Spunk was an important material, certainly in a man`s youthful years. Loss of seed by manual manipulation was life-threatening. Without seed no nerves and no brains.
Boys pleasuring themselves too often were tearing down their constitution, would get spinal consumption and eventually die or would commit suicide. Tissot initiated a tradition. After his first step hundreds of book came out about onanism.
According to Tissot and consorts causes for self-gratification were culturally determined. Boys learned to masturbate from other boys, from bad educators and by reading the wrong literature.
It could be that the beds they slept in were too warm, that they slept on their stomach and not on their back, were riding horse or glided down banisters, ate hot and spicy foods or red meat, drank coffeee, tea or alcohol, got to know the pleasures of physical touch while urinating, etcetera.
Some educators even warned against reading the Bible, because this could arouse feelings of lust. On the rebound Tissot demanded from parents and educators to control the entire life of their children in order to turn the evil tide of self-stimulation.
Historians have claimed that the battle against onanism has had less of an effect on the habit itself than on the boys` upbringing.