But in the real genesis of actual languages, the process does not take place either in the same direction or with the same rigour: on the basis of primitive designations, men's imaginations (according to the climates they live in, the conditions of their existence, their feelings and their passions, their experiences) give rise to derivations which differ from people to people, and which doubtless explain, in addition to the diversity of languages, the relative instability of each of them.