The first Trope, we said, is the one based upon the 40 differences in animals, and according to this Trope, different animals do not get the same ideas of the same objects through the senses.  This we conclude from the different origin of the animals, and also from the difference in the constitution of their bodies.  In regard to the difference in origin, some animals originate without mixture of the sexes, while others originate through sexual intercourse.  Of those which 41 originate without intercourse of the sexes, some come from fire, as the little animals which appear in the chimneys, others from stagnant water, as musquitoes, others from fermented wine, as the stinging ants, others from the earth, others from the mud, like the frogs, others from slime, as the worms, others from donkeys, as the beetles, others from cabbage, as caterpillars, others from fruit, as the gall insect from the wild figs, others from putrified animals, as bees from bulls, and wasps from horses.  Again, of those originating from intercourse of the 42 sexes, some come from animals of the same kind, as in most cases, and others from those of different kinds, as mules.  Again, of animals in general, some are born alive, as men, others from eggs, as birds, and others are born a lump of flesh, as bears.  It is probable therefore, that the inequalities and 43 differences in origin cause great antipathies in the animals, and the result is incompatibility, discord, and conflict between the sensations of the different animals.  Again, the differences in the principal parts of the body, especially in those 44 fitted by nature to judge and to perceive, may cause the greatest differences in their ideas of objects, according to the differences in the animals themselves.  As for example, those who have the jaundice call that yellow which appears to us white, and those who have bloodshot eyes call it blood-red.  Accordingly, as some animals have yellow eyes, and others blood-shot ones, and still others whitish ones, and others eyes of other colors, it is probable, I think, that they have a different perception of colors.  Furthermore, when we look steadily at the sun for a long time, and then look down at a 45 book, the letters seem to us gold colored, and dance around.  Now some animals have by nature a lustre in their eyes, and these emit a fine and sparkling light so that they see at night, and we may reasonably suppose that external things do not appear the same to them as to us.  Jugglers by lightly rubbing the wick 46 of the lamp with metal rust, or with the dark yellow fluid of the sepia, make those who are present appear now copper-colored and now black, according to the amount of the mixture used; if this be so it is much more reasonable to suppose that because of the mixture of different fluids in the eyes of animals, their ideas of objects would be different.  Furthermore, when we 47 press the eye on the side, the