“The world as we have created it is a process of our thinking. It cannot be changed without changing our thinking.”

“I speak to everyone in the same way, whether he is the garbage man or the president of the university.”

“Did you know: The only source of knowledge is experience” 

“Out of clutter, find simplicity. From discord, find harmony. In the middle of difficulty lies opportunity.”

“Common sense is the collection of prejudices acquired by age eighteen.”

“Oh juventud nunca dejes de pensar...”

“We are in the position of a little child, entering a huge library whose walls are covered to the ceiling with books in many different tongues. The child knows that someone must have written those books. It does not know who or how. It does not understand the languages in which they are written. The child notes a definite plan in the arrangement of the books, a mysterious order, which it does not comprehend, but only dimly suspects. That, it seems to me, is the attitude of the human mind, even the greatest and most cultured, toward God. We see a universe marvelously arranged, obeying certain laws, but we understand the laws only dimly. Our limited minds cannot grasp the mysterious force that sways the constellations.”

“Nobody knows how the stand of our knowledge about the atom would be without him. Personally, Bohr is one of the amiable colleagues I have met. He utters his opinions like one perpetually groping and never like one who believes himself to be in possession of the truth.”

“If at first the idea is not absurd, then there is no hope for it.”

“The most important human endeavor is the striving for morality in our actions. Our inner balance and even our very existence depend on it. Only morality in our actions can give beauty and dignity to life. To make this a living force and bring it to clear consciousness is perhaps the foremost task of education. The foundation of morality should not be made dependent on myth nor tied to any authority lest doubt about the myth or about the legitimacy of the authority imperil the foundation of sound judgment and action.”

“Three Rules of Work: Out of clutter find simplicity. From discord find harmony. In the middle of difficulty lies opportunity.”

“I gang my own gait and have never belonged to my country, my home, my friends, or even my immediate family, with my whole heart; in the face of all these ties I have never lost an obstinate sense of detachment, of the need for solitude — a feeling which increases with the years.”

“The value of a man should be seen in what he gives and not in what he is able to receive.”

“God always takes the simplest way.”

“The tendencies we have mentioned are something new for America. They arose when, under the influence of the two World Wars and the consequent concentration of all forces on a military goal, a predominantly military mentality developed, which with the almost sudden victory became even more accentuated. The characteristic feature of this mentality is that people place the importance of what Bertrand Russell so tellingly terms “naked power” far above all other factors which affect the relations between peoples. The Germans, misled by Bismarck’s successes in particular, underwent just such a transformation of their mentality—in consequence of which they were entirely ruined in less than a hundred years. I must frankly confess that the foreign policy of the United States since the termination of hostilities has reminded me, sometimes irresistibly, of the attitude of Germany under Kaiser Wilhelm II, and I know that, independent of me, this analogy has most painfully occurred to others as well. It is characteristic of the military mentality that non-human factors (atom bombs, strategic bases, weapons of all sorts, the possession of raw materials, etc.) are held essential, while the human being, his desires and thoughts—in short, the psychological factors—are considered as unimportant and secondary. Herein lies a certain resemblance to Marxism, at least insofar as its theoretical side alone is kept in view. The individual is degraded to a mere instrument; he becomes “human materiel.” The normal ends of human aspiration vanish with such a viewpoint. Instead, the military mentality raises “naked power” as a goal in itself—one of the strangest illusions to which men can succumb.”