Louie Pasteur on why he did his experiments to disprove Darwins newly popular theory and its foundation of spontaneous generation:
” It is dumb, dumb since these experiments were begun several years ago; it is dumb because I have kept it sheltered from the only thing man does not know how to produce, from the germs which float in the air, from Life, for Life is a germ and a germ is Life. Never will the doctrine of spontaneous generation recover from the mortal blow of this simple experiment! “No, there is now no circumstances known in which it could be affirmed that microscopic beings come into the world without germs, without parents, similar to themselves”.
(Vallery-Radot 1901, vol. 1, p. 142).