Evolution is not finished; reason is not the last word nor the reasoning animal the supreme figure of Nature. As man emerged out of the animal, so out of man the superman emerges.
Memory is therefore, neither Perception nor Conception, but a state or affection of one of these, conditioned by lapse of time. As already observed, there is no such thing as memory of the present while present, for the present is object only of perception, and the future, of expectation, but the object of memory is the past. All memory, therefore, implies a time elapsed; consequently only those animals which perceive time remember, and the organ whereby they perceive time is also that whereby they remember.
I am not interested to know whether vivisection produces results that are profitable to the human race or doesn't...The pain which it inflicts upon unconsenting animals is the basis of my enmity toward it, and it is to me sufficient justification of the enmity without looking further.
For man, when perfected, is the best of animals, but, when separated from law and justice, he is the worst of all; since armed injustice is the more dangerous, and he is equipped at birth with the arms of intelligence and with moral qualities which he may use for the worst ends. Wherefore, if he have not virtue, he is the most unholy and the most savage of animals, and the most full of lust and gluttony. But justice is the bond of men in states, and the administration of justice, which is the determination of what is just, is the principle of order in political society.
It is a law of nature we overlook, that intellectual versatility is the compensation for change, danger, and trouble. An animal perfectly in harmony with its environment is a perfect mechanism. Nature never appeals to intelligence until habit and instinct are useless. There is no intelligence where there is no change and no need of change. Only those animals partake of intelligence that have a huge variety of needs and dangers.
Nothing can be more shocking and horrid than one of our kitchens sprinkled with blood, and abounding with the cries of expiring victims or with the limbs of dead animals scattered or hung up here and there.
... man was not born a carnivorous animal, but born to live on the fruits and herbs that the earth grows. I know we must all err. I would give up milk if I could, but I cannot. I have made that experiment times without number. I could not, after a serious illness, regain my strength, unless I went back to milk. That has been the tragedy of my life. But the basis of my vegetarianism is not physical, but moral. If anybody said that I should die if I did not take beef tea or mutton, even on medical advice, I would prefer death. That is the basis of my vegetarianism.
Plants, again, inasmuch as they are without locomotion, present no great variety in their heterogeneous pacts. For, when the functions are but few, few also are the organs required to effect them. ... Animals, however, that not only live but perceive, present a great multiformity of pacts, and this diversity is greater in some animals than in others, being most varied in those to whose share has fallen not mere life but life of high degree. Now such an animal is man.
I can no more explain why I like "natural history" than why I like California canned peaches; nor why I do not care for that enormous brand of natural history which deals with invertebrates any more than why I do not care for brandied peaches. All I can say is that almost as soon as I began to read at all I began to like to read about the natural history of beasts and birds and the more formidable or interesting reptiles and fishes.
The animal tends to eat with his stomach, and the man with his brain. When the animal's stomach is full, he stops eating, but the man is never sure when to stop. When he has eaten as much as his belly can take, he still feels empty, he still feels an urge for further gratification.