On Youth And Old Age, On Life And Death, On Breathing   

element preponderating in the scheme of their constitution that things

exist.



20



Empedocles is then in error when he says that those animals which

have the most warmth and fire live in the water to counterbalance

the excess of heat in their constitution, in order that, since they

are deficient in cold and fluid, they may be kept in life by the

contrary character of the region they occupy; for water has less

heat than air. But it is wholly absurd that the water-animals should

in every case originate on dry land, and afterwards change their place

of abode to the water; for they are almost all footless. He,

however, when describing their original structure says that, though

originating on dry land, they have abandoned it and migrated to the

water. But again it is evident that they are not warmer than

land-animals, for in some cases they have no blood at all, in others

little.

The question, however, as to what sorts of animals should be

called warm and what cold, has in each special case received

consideration. Though in one respect there is reason in the

explanation which Empedocles aims at establishing, yet his account

is not correct. Excess in a bodily state is cured by a situation or

season of opposite character, but the constitution is best

maintained by an environment akin to it. There is a difference between

the material of which any animal is constituted and the states and

dispositions of that material. For example, if nature were to

constitute a thing of wax or of ice, she would not preserve it by

putting it in a hot place, for the opposing quality would quickly

destroy it, seeing that heat dissolves that which cold congeals.

Again, a thing composed of salt or nitre would not be taken and placed

in water, for fluid dissolves that of which the consistency is due