There is no fundamental difference between man and animals in their ability to feel pleasure and pain, happiness, and misery.

But I own that I cannot see as plainly as others do, and I should wish to do, evidence of design and beneficence on all sides of us. There seems to me too much misery in the world. I cannot persuade myself that a beneficent and omnipotent God would have designedly created that a cat should play with mice.

I ought, or I ought not, constitute the whole of morality.

Man himself cannot express love and humility by external signs, so plainly as does a dog, when with drooping ears, hanging lips, flexuous body, and wagging tail, he meets his beloved master.

From the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of higher animals, directly follows.

The season of love is that of battle. The roots of these fights run deep.

The lower animals, like man, manifestly feel pleasure and pain, happiness and misery. Happiness is never better exhibited than by young animals, such as puppies, kittens, lambs, &c., when playing together, like our own children.