Tolstoy's views toward animals changed drastically throughout his life (as pretty much everything did). In his youth and much of his middle age, he was an avid hunter. In fact, Book Seven of War and Peace is devoted almost exclusively to a wolf hunt. When I first read this, it was through the eyes of someone familiar with Tolstoy's later love of animals, and the description of the capture of the wolf was so gruesome that I thought it was an indictment of hunting. But apparently at that point in his life Tolstoy had wanted for some time to write a description of a wolf hunt.
His attitude toward animals began to change in the 1880s, after his conversion. First he gave up hunting. He didn't object to his sons' hunting, but asked them not to bring the game into the house when he was there. But before 1900 he had become a vegetarian and a strong proponent of the notion that animals and humans are equal:
You must treat animals as well as people the way you’d like to be treated. (For Every Day, January 3, entry 7)
There was a time when people ate human flesh and found nothing wrong with it. Then the best people understood that it’s bad, and people began little by little to wean themselves off human flesh, and now they’ve become so weaned from it that people are horrified to think about eating their brothers. In the same way, many people are already realizing that it’s bad to eat animals, and there are more and more of these people all the time. Soon the time will come when people will be just as horrified at the thought of killing a sheep, cow or pig in order to eat it as they are now at the thought of killing a human in order to eat him. (February 3, entry 3)
People don’t consider it base to eat animals because false teachers have convinced them that animals have been designated by God for people’s exploitation. This is a lie. It doesn’t matter in what book it’s written that it’s not a sin to kill animals, it is written more clearly in everyone’s hearts than in any book that one mustn’t kill animals, but rather one must sympathize with them just like with people. We all know this, unless we’ve silenced the conscience within us. (March 3, entry 2)
In order that life not be suffering but rather total joy one must always be kind to all, both people and animals. And in order to always be kind one must learn how. And in order to learn how you must never let a single bad deed pass by without reproaching yourself for it.
Do this and soon you’ll become accustomed to being kind to all people and animals. And if you become accustomed to kindness, there will always be joy in your heart. (May 20, entry 1)
Ultimately, Tolstoy equates all life:
We feel that the main thing by means of which we live, that which we call our true “I,” is the same not only for every person, but for dogs, horses, mice, chickens, sparrows, bees, even trees. (February 3, entry 1)
He also equates violence against animals with violence in human society:
As long as there are slaughter houses there will always be battlefields.
I think one of the experiences that made Tolstoy such a confirmed vegetarian and supporter of animal rights was a visit he paid to a slaughterhouse in the early 1890s. He records his experience in “The FirstStep,” which he wrote as a preface to Howard Williams’ The Ethics of Diet. It’s a vivid description of what happens in a slaughterhouse and the reactions of the men who participate in the killing.
Some of Tolstoy’s children became vegetarians, although his wife strongly objected and even coerced some of them into returning to eating meat. Tolstoy, however, remained a vegetarian to the end of his life. He tied it to spiritual development at much as does Hindu philosophy.
If a person sincerely seeks a righteous life, his first act of abstinence is from animal food.
Since vegetarianism is a fundamental part of the Hindu concept of Ahimsa (non-violence), we can see a very close correlation between Tolstoy’s thought and that of the Vedanta. A comprehensive comparison would be very interesting.