D O C U M E N T 4 3 3 D E C E M B E R 1 9 2 6 4 1 1 433. From Eduard Einstein Zurich, 12 December  Dear Papa, Many thanks for your letter. I sensed a certain irritation in it, [which], to my astonishment, seemed to be provoked by the harmless word salad that I sent you shortly before that. I suspect that you took this somewhat too seriously. You insin- uated ideas into my chatter that were quite alien to me. It seems that extremely harmless ideas become brash and arrogant if one writes them down. At least, it seems so in my case. It may also have resulted from the fact that I somehow wish to underscore my ideas, which are in and of themselves dubious and, beyond that, insignificant. I recognize that, for another person, that can be seen as annoying. Ar- rogance is one of the characteristics that a person countenances only in himself. Nevertheless, there are in your letter a few points that I felt the need to contra- dict. But your letter is so subtle that it presents difficulties. When you declare that you have contemplated such problems throughout your entire life, I can counter you with absolutely nothing of equal status. When you state that you entertained the same ideas as I during your youth, the suspicion has to arise in me that it would be completely futile to argue with you, since you are certainly in every respect at least 30 years ahead of me. I also believe that it is futile however, that is no reason to refrain from it. What you say (for example) about intellectual work does not seem totally con- vincing to me. You say that Eudaimonia is a pathetic swine-herd ideal. But now I must ask you why you actually occupy yourself with science. Obviously not for any far-fetched reasons, but because you find satisfaction in it. Thus you say ap- proximately: “That all people should be happy, is a pathetic ideal. I behave in such a way that I, I, I am happy.” That is virtually the same thing that I also think. I would certainly not say something if you, for example, had an aversion to science and you nevertheless would dedicate yourself to it out of some sort of convictions and then it would still need to be investigated whether your satisfaction did not con- sist in your being able to saddle yourself with something unpleasant. Besides, I do not find Eudaimonia such a pathetic ideal at all. Nature obviously implanted us with the sensation of happiness and of pain to motivate us to do what is favorable to life. To seek one’s goal in living happily thus means, under normal circumstances, seeking to live in accordance with nature. The person who wishes to oppose the natural ¢circumstances² instincts resembles a windmill that does, in fact, wish to run, but in the opposite direction than the wind is blowing.