Do you know any vegan or vegetarian philosophers?
Let list all of them here.
From what i know Einstein wrote some philosophic works.
Pythagoras was a vegan philosopher AFAIK.
Diogenes too.
Is Tolstoy a philosopher? Jethro Kloss?
IMHO Tolstoy was just a bored rich man 
Why do you think so?
It is a known fact he was rich.
I can hardly imagine another reason than boredom for writing such huge books
lol 
May be he wanted to share his thoughts with people… there were no forums then… 
so he couldn’t troll around with his ideas…
But seriously he was a great philosopher of his time and he was vegan. He wrote “The First Step” which is about veganism.
Nowadays Tolstoy would be classified as forum spammer.
Judging by the size of his books 
Gary L. Francione is a vegan philosopher.
Warchild, yes Diogenes was a philosopher in the antic Greece. He is said to have lived in a large tub, rather than a house, and to have walked through the streets carrying a lamp in the daytime, claiming to be looking for a honest man.
But I couldn’t find anything about him being vegan or not.
Empedocles on the other hand was known to be vegetarian.
Plutarch was an ancient vegetarian philosopher (c.AD 46 - c.120)
Here is a quote from his work - “Moralia” :
Gautama Buddha is a very ancient and vegan philosopher.
Vegan Philosophers is not a great name for a topic since the term vegan is quite new and it is almost impossible to be sure if any of the ancient philosophers were truly vegan. I would suggest changing the name of the topic to vegetarian philosophers.
Porphyry (234?–305? C.E.) was a vegetarian Neoplatonist philosopher born in Tyre in Phoenicia. He studied with Longinus in Athens and then with Plotinus in Rome from 263–269 C.E. and became a follower of the latter’s version of Platonism. Porphyry wrote in just about every branch of learning practiced at the time but only a portion of his large output is extant. Porphyry was an influential thinker. He applied Neoplatonism to pagan religion and other spheres and is as such a key figure the promulgation of Neoplatonic thought. His writings on Aristotle’s logical works, preserved in part and influential in the Latin West through Boethius’ translations, contain attempts to harmonize Aristotle’s logical writings with Platonism.
He wrote the On Abstinence from Eating Food from Animals where he describes a vegan philosophy.
I am a philosopher by trade.
In the philosophical community, Peter Singer is by far the best known and most vocal proponent of vegetarianism. He is an Australian, but many Americans will have heard his name from his books and his sometime position at Princeton.
If you read his articles, be forewarned that he is an unapologetic utilitarian, so many of his arguments may seem rather abrasive. Just try to keep in mind that there are no “mean” arguments in philosophy…just sound ones and unsound ones, valid and invalid ones, etc.
I think Mohandas Karamchand Gandhi A.K.A. Mahatma Gandhi was one.