The question is not, "Can they reason?" nor, "Can they talk?" but "Can they suffer?” 

As long as Man continues to be the ruthless destroyer of lower living beings, he will never know health or peace.

The thinking man must oppose all cruel customs no matter how deeply rooted in tradition and surrounded by a halo. When we have a choice, we must avoid bringing torment and injury into the life of another, even the lowliest creature; to do so is to renounce our manhood and shoulder a guilt which nothing justifies. 

The thought of two thousand people crunching celery at the same time horrified me.

Man, do not pride yourself on superiority to animals.

A sharp distinction between humans and “animals” is essential if we are to bend them to our will, make them work for us, wear them, eat them–without any disquieting tinges of guilt or regret. It is unseemly of us, who often behave so unfeeling toward other animals, to contend that only humans can suffer. The behavior of other animals renders such pretensions specious. They are just too much like us.

Life is as dear to a mute creature as it is to a man. Just as one wants happiness and fears pain, just as one wants to live and not to die, so do other creatures.

I'd like everybody to be a vegetarian... In 100 or 200 years time, we may look back on the way we treated animals today as something like we today look back on the way our forefathers treated slaves.

What do they know-all these scholars, all these philosophers, all the leaders of the world - about such as you? They have convinced themselves that man, the worst transgressor of all the species, is the crown of creation. All other creatures were created merely to provide him with food, pelts, to be tormented, exterminated. 

I have from an early age abjured the use of meat, and the time will come when men such as I will look upon the murder of animals as they now look upon the murder of men.