If you want to find out anything from the theoretical physicists about the methods they use, I advise you to stick closely to one principle: don't listen to their words, fix your attention on their deeds. To him who is a discoverer in this field the products of his imagination appear so necessary and natural that he regards them, and would like to have them regarded by others, not as creations of thought but as given realities.
Since that deluge of newspaper articles I have been so flooded with questions, invitations, suggestions, that I keep dreaming I am roasting in Hell, and the mailman is the devil eternally yelling at me, showering me with more bundles of letters at my head because I have not answered the old ones.
In conclusion I wish to say that in working at the problem here dealt with I have had the loyal assistance of my friend and colleague M. Besso, and that I am indebted to him for several valuable suggestions.
Man is, at one and the same time, a solitary being and a social being. As a solitary being, he attempts to protect his own existence and that of those who are closest to him, to satisfy his personal desires, and to develop his innate abilities. As a social being, he seeks to gain the recognition and affection of his fellow human beings, to share in their pleasures, to comfort them in their sorrows, and to improve their conditions of life.
Man tries to make for himself in the fashion that suits him best a simplified and intelligible picture of the world; he then tries to some extent to substitute this cosmos of his for the world of experience, and thus to overcome it. This is what the painter, the poet, the speculative philosopher, and the natural scientists do, each in his own fashion. Each makes this cosmos and its construction the pivot of his emotional life, in order to find in this way peace and security which he can not find in the narrow whirlpool of personal experience.
Relations between pure and applied mathematicians are based on trust and understanding.
Namely, pure mathematicians do not trust applied mathematicians, and applied mathematicians do not understand pure mathematicians.
The world we have made as a result of the level of thinking we have
done thus far creates problems that we cannot solve at the same level at which we have created them.... We shall require a substantially new manner of thinking if humankind is to survive.
Some men spend a lifetime in an attempt to comprehend the complexities of women. Others pre-occupy themselves with somewhat simpler tasks, such as understanding the theory of relativity!
We must remember that we do not observe nature as it actually exists, but nature exposed to our methods of perception. The theories determine what we can or cannot observe...Reality is an illusion, albeit a persistent one.
I believe, indeed, that overemphasis on the purely intellectual attitude, often directed solely to the practical and factual, in our education, has led directly to the impairment of ethical values.
I would absolutely refuse any direct or indirect war service and would try to persuade my friends to do the same, regardless of the reasons for the cause of a war.