Man is an essentially superstitious and fearful animal. Take away the herd's Christian gods and saints and they will without failing come to worship...something else.
There is no character, howsoever good and fine, but it can be destroyed by ridicule, howsoever poor and witless. Observe the ass, for instance: his character is about perfect, he is the choicest spirit among all the humbler animals, yet see what ridicule has brought him to. Instead of feeling complimented when we are called an ass, we are left in doubt.
He had been content with daily labour and rough animal enjoyments, 'till Catherine crossed his path. Shame at her scorn, and hope of her approval, were his first prompts to higher pursuits; and, instead of guarding him from one and winning him to the other, his endeavors to raise himself had produced just the contrary result.
Plants, again, inasmuch as they are without locomotion, present no great variety in their heterogeneous pacts. For, when the functions are but few, few also are the organs required to effect them. ... Animals, however, that not only live but perceive, present a great multiformity of pacts, and this diversity is greater in some animals than in others, being most varied in those to whose share has fallen not mere life but life of high degree. Now such an animal is man.
The higher animals get their teeth without pain or inconvenience. Man gets his through months and months of cruel torture; he will never get a set which can really be depended on 'till a dentist makes him one.
He hath not eat paper, as it were; he hath not drunk ink; his intellect is not replenished; he is only an animal, only sensible in the duller parts. (Shakespeare, Love's Labor's Lost, IV)
My point is, I don't see the need to eat animals. I love animals; besides the horrible stuff that's put in meat, I actually love cuddling with animals and petting them and stuff.
And not only did he learn by experience, but instincts long dead became alive again. The domesticated generations fell from him. In vague ways he remembered back to the youth of the breed, to the time the wild dogs ranged in packs through the primeval forest and killed their meat as they ran it down.