People must have renounced, it seems to me, all natural intelligence to dare to advance that animals are but animated machines.... It appears to me, besides, that such people can never have observed with attention the character of animals, not to have distinguished among them the different voices of need, of suffering, of joy, of pain, of love, of anger, and of all their affections. It would be very strange that they should express so well what they could not feel.
It is with books as with the fires of our grates, everybody borrows a light from his neighbor to kindle his own, which in turn is communicated to others, and each partakes of all.
Opinion is called the queen of the world; it is so, for when reason opposes it, it is condemned to death. It must rise twenty times from its ashes to gradually drive away the usurper.
I also know that we must cultivate our garden. For when man was put in the Garden of Eden, he was put there ut operaretur eum, to work; which proves that man was not born for rest.