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.
One can generally say this about men: that they are ungrateful, fickle, simulators and deceivers, avoiders of danger, greedy for gain; and while you work for their good they are completely yours, offering you their blood, their property, their lives, and their sons when danger is far away; but when it comes nearer to you, they turn away.