Abstract
" Genetics," a mathematician friend once told me, "smells a bit like apples and snakes. " I'm afraid that the smell today is much less poetic, as it has gradually become impregnated with chemistry. At the heart of biology, genetics is currently in a state of turmoil. Its place at the Collège de France is therefore justified. It also means that the task of teaching it here is both easy and arduous. Easy, because having to demonstrate the twists and turns of knowledge in constant motion can only be a source of exaltation for the man of science. Difficult, because, in the whirlwind of ideas, discoveries and hypotheses, and in the very agitation of one's own thoughts, it's a daunting task to maintain sufficient order and rigor to communicate such a shifting equilibrium..
