after the principle of horses fashioned in bronze with their

forelegs prancing. But their being bipeds and able to stand is above

all due to their having the hip-bone shaped like a thigh, and so large

that it looks as if they had two thighs, one in the leg before the

knee-joint, the other joining his part to the fundament. Really this

is not a thigh but a hip, and if it were not so large the bird could

not be a biped. As in a man or a quadruped, the thigh and the rest

of the leg would be attached immediately to quite a small hip;

consequently the whole body would be tilted forward. As it is,

however, the hip is long and extends right along to the middle of

the belly, so that the legs are attached at that point and carry as

supports the whole frame. It is also evident from these considerations

that a bird cannot possibly be erect in the sense in which man is. For

as it holds its body now the wings are naturally useful to it, but

if it were erect they would be as useless as the wings of Cupids we

see in pictures. It must have been clear as soon as we spoke that

the form of no human nor any similar being permits of wings; not

only because it would, though Sanguineous, be moved at more than

four points, but also because to have wings would be useless to it

when moving naturally. And Nature makes nothing contrary to her own

nature.

12



We have stated above that without flexion in the legs or shoulders

and hips no Sanguineous animal with feet could progress, and that

flexion is impossible except some point be at rest, and that men and

birds, both bipeds, bend their legs in opposite directions, and

further that quadrupeds bend their in opposite directions, and each

pair in the opposite way to a man's limbs. For men bend their arms

backwards, their legs forwards; quadrupeds their forelegs forwards,

their back legs backwards, and in like manner also birds bend

theirs. The reason is that Nature's workmanship is never