CHAP. 92. (39.)—WHETHER THE BLOOD IS THE PRINCIPLE OF
LIFE.
There are some persons who are of opinion that the fineness
of the wit does not depend upon the thinness of the blood, but
that animals are more or less stupid in proportion to the skin
or other coverings of the body, as the oyster and the tortoise,
for instance: that the hide of the ox and the bristles of the hog,
in fact, offer a resistance to the fine and penetrating powers of
the air, and leave no passage for its transmission in a pure
and liquid state. The same, they say, is the case, too, with
men, when the skin is very thick or callous, and so excludes
the air. Just as if, indeed, the crocodile was not equally remarkable for the hardness of its skin and its extreme cunning.