Not until the creation and maintenance of decent conditions of life for all men are recognized and accepted as a common obligation of all men and all countries — not until then shall we, with a certain degree of justification, be able to speak of mankind as civilized.
Every thoughtful, well-meaning and conscientious human being
should assume in time of peace,
the solemn and unconditional obligation
not to participate in any war, for any reason
or to lend support of any kind, whether direct or indirect.
Consider the concepts referred to in the words 'where', 'when', 'why', 'being', to the elucidation of which innumerable volumes of philosophy have been devoted. We fare no better in our speculations than a fish which should strive to become clear as to what is water.
The years of searching in the dark for a truth that one feels but cannot express, the intense desire and the alternations of confidence and misgiving until one breaks through to clarity and understanding, are known only to him who has experienced them himself.
Live life to the fullest. You have to color outside the lines once in a while if you want to make your life a masterpiece. Laugh some every day. Keep growing, keep dreaming, keep following your heart. The important thing is not to stop questioning.
However we select from nature a complex [of phenomena] using the criterion of simplicity, in no case will its theoretical treatment turn out to be forever appropriate (sufficient).... I do not doubt that the day will come when [general relativity], too, will have to yield to another one, for reasons which at present we do not yet surmise. I believe that this process of deepening theory has no limits.
There exists a passion for comprehension, just as there exists a passion for music. That passion is rather common in children, but gets lost in most people later on. Without this passion there would be neither mathematics nor natural science.
We should be on our guard not to overestimate science and scientific methods when it is a question of human problems, and we should not assume that experts are the only ones who have the right to express themselves on questions affecting the organization of society.
Each ray of light moves in the coordinate system 'at rest' with the definite, constant velocity V independent of whether this ray of light is emitted by a body at rest or a body in motion.