Since the dawn of history, man has been in urgent need of a system of values and ideals, which prompted him to re-examine more precisely his biological center, and the fact remains, as the gap between man and animal widens once again. After Darwin''s theory, man could no longer avoid considering himself an animal, but he began to see himself as a very strange animal, and in many cases unparalleled. The analysis of human uniqueness from a biological standpoint is still incomplete.Man''s opinion regarding his position in relation to the rest of the animals has fluctuated between his great or little admiration for himself, separated from the animals at times by a very deep gulf, and at other times by a very small gulf. It is of course possible to reduce or enlarge the gap, either on the animal side or on the human side. A person can - as Descartes did - depict animals as machines - or - as most naive people do - that is, give them many human characteristics, or a person can work on the human side of the abyss, and then he either strips his human race of its characteristics, and enters it into... He is compared to animals, or he is elevated to such an extent that he is slightly lower than angels.
