20. One naturally asks: why have there not been formed more living beings in the same conditions as the first to appear on Earth?
The question of abiogenesis with which science is occupied today, although yet diversely decided upon, cannot fail to throw light upon this subject. The problem proposed is this: are there spontaneously formed in our day organic beings by the sole union of the constituent elements without previous germs produced by ordinary generation, i.e., without fathers or mothers?
The partisans of abiogenesis reply affirmatively, and are supported by direct observations, which seem conclusive. Others think that all living beings are reproduced by one another, and support this fact arrived at by experience, as the germs of certain vegetable and animal species, being dispersed, can preserve a latent vitality for a considerable time until circumstances are favorable to their birth. This opinion does not answer any question concerning the formation of the first parents of any species.