I think you are thinking of Pythagoras. Aristoteles was the main influence on Christian western philosophy cementing the oppression of animals. Suggested reading: in defense of Animals, Ed. Peter Singer.

There was an active vegetarian debate in classical greece which Aristotle help put to
an end by arguing that only white males where capable of reason and therefore worthy of moral concern. Women, slaves and animals where not to be considered.

Please correct this list so as not confuse potential readers and help explain why change is possible also when it comes to
animals.

No, Aristotle was not vegetarian. Where are you getting this stuff. You are not helping the cause of animal rights/veganism by publishing this nonsense.

"Plants exist for the sake of animals, and brute beasts for the sake of man..." - Aristotle, The Politics

These are not the words of a vegetarian. It is significantly unlikely Aristotle was vegetarian.

IF HE *WAS* VEGETARIAN HE WAS A G :)

I disagree. There is no proof for Aristotle being a vegetarian, and i think this page is misleading to those who know less. If you google, 'the works of aristotle' and read 'of the stomach' that is the proof of aristotle 'not' being a vegetarian. Here is an excerpt from the page:

Why is it unwholesome to stay long for one dish after another and to eat of divers kinds of meat?
Because the first begins to digest when the first is eaten and so the digestion is not equally made, and therefore the meat digested beginneth to corrupt. But yet this rule is to be noted touching the order of meat, that if there be any dishes, whereof some are light of digestion, as chickens, kid, veal, soft eggs, and such like, these meats should be first eaten; but gross meats, as venison, bacon, beef, roast pork, hard eggs, and fried eggs, should be eaten last.

what evidence is there that Aristotle was a vegetarian?

I read some Aristotle work in college while studying western philosophy, and I must say I enjoyed his thinking and style. Cool dude.