"Compassion, in which all ethics must take root, can only attain its full breadth and depth if it embraces all living creatures and does not limit itself to mankind."

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When man learns to respect even the smallest being of creation...nobody has to teach him to love his fellow man. Compassion for animals is intimately connected with goodness of character, and it may be confidently asserted that he who is cruel to animals cannot be a good man.

— Albert Schweitzer