The little animals had got themselves involved in a strange question, in a furious fight, and had it not been for that, they might have remained curiosities for centuries, or even have been completely forgotten. This argument, over which dear friends grew to hate each other and about which professors tried to crack the skulls of priests, was briefly this: Can living things arise spontaneously, or does every living thing have to have parents? Did God create every plant and animal in the first six days, and then settle down to be Managing Director of the universe, or does He even now amuse Himself by allowing new animals to spring up in humorous ways? In Spallanzani’s time the popular side was the party that asserted that life could arise spontaneously. The great majority of sensible people believed that many animals did not have to have parents--that they might be the unhappy illegitimate children of a disgusting variety of dirty messes. Here, for example, was a supposedly sure recipe for getting yourself a good swarm of bees. Take a young bullock, kill him with a knock on the head, bury him under the ground in a standing position with his horns sticking out. Leave him there for a month, then saw off his horns--and out will fly your swarm of bees. II Even the scientists were on this side of the question. The English naturalist Ross announced learnedly that: “To question that beetles and wasps were generated in cow dung is to question reason, sense, and experience.” Even such complicated animals as mice didn’t have to have mothers or fathers--if anybody doubted this, let him go to Egypt, and there he would find the fields literally swarming with mice, begot of the mud of the River Nile--to the great calamity of the inhabitants! Spallanzani heard all of these stories which so many important people were sure were facts, he read many more of them that were still more strange, he watched students get into brawls in excited attempts to prove that mice and bees didn’t have to have fathers or mothers. He heard all of these things--and didn’t believe them. He was prejudiced. Great advances in science so often start from prejudice, on ideas got not from science but straight out of a scientist’s head, on notions that are only the opposite of the prevailing superstitious nonsense of the day. Spallanzani had violent notions about whether life could rise spontaneously; for him it was on the face of things absurd to think that animals--even the wee beasts of Leeuwenhoek--could arise in a haphazard way from any old thing or out of any dirty mess. There must be law and order to their birth, there must be a rime and reason! But how to prove it?