"Observe the herd which is grazing beside you. It does not know what yesterday or today is. It springs around, eats, rests, digests, jumps up again, and so from morning to night and from day to day, with its likes and dislikes closely tied to the peg of the moment, and thus is neither melancholy nor weary. To witness this is difficult for man, because he boasts to himself that his human condition is better than the beast’s and yet looks with jealousy at its happiness. For he wishes only to live like the beast, neither weary with things nor in pain, and yet he wants it in vain, because he does not desire it as the animal does."
Friedrich Nietzsche, On the Use and Abuse of History for Life
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