Phaedo — I do not know how we can tell which is superior.  The primordial cell in differentiating out of homogeneity into heterogeneity developed different qualities in different beings, and of the organs integrated from the heterogeneous elements each has its use and many are essential to life.  In man the brain is more powerful than in the ox, but in the ox the stomach is more powerful than the brain, and while both stomach and brain are necessary, yet is one with a weak brain and strong stomach doubtless happier than one with a weak stomach and strong brain.  Is it not, then, true that the stomach is nobler than the brain, and if so, then the pig and the lion and the goat, which have strong stomachs, nobler than man, whose stomach could in nowise digest carrion, or alfalfa, or tin cans, and therefore may it not be that the earth was made for the lower animals, who can use more of its products than man?

Socrates — That is a deep thought, O Phaedo, which shows that you are well up in your Spencer, although shy in your surgery, for it is true that the stomach has been removed from a man who lived happy ever after, while neither man nor beast ever lived a minute after his brains were knocked out; but, is it not true that it is by the function of the brain that man makes his powers more effective than those of animals stronger than he, so that he is able to bear rule over all the lower animals and either exterminate them from the earth or make them to serve him?

Phaedo — Yes, that is true.

Socrates — And we cannot say that the earth was made for beasts which themselves are made to serve the purpose of man, for as plants are consumed by beasts, so beasts are consumed by man who acquires for his own use and enjoyment whatever power is generated by the organs of all other living things.

Phaedo — That is true, and I can now see that the earth was not made by the gods for themselves, or for plants or beasts.

Socrates — Therefore, it appears to me that it must have been made for man.

Phaedo — That is true, and I now agree that the earth was made for man.

Socrates — Then, since we have found a common starting point, we may go on with our conversation.  We have proved that the earth was made for man, because man, by powers inherent in himself, can overcome all other living things on the earth and subject them to his uses.

Phaedo — Yes, we have proved that.

Socrates — And the real source of his kingship is power.

Phaedo — That must be true.

Socrates — And force is power applied to some object, so that power and force may be spoken of as the same thing.

Phaedo — Certainly.

Socrates — And where power lies, there and there only is sovereignty, and where power ends sovereignty finds its limit.  So that, for example, if the lion could subdue man and the other animals, the earth would be for the use of the lion.