One reason why mathematics enjoys special esteem,above all other sciences,is
that its laws are absolutely certain and indisputable,while those of all
other sciences are to some extent debatable and in constant danger of being
overthrown by newly discovered facts.
To know what is impenetrable to us really exists, manifesting itself as the highest wisdom and the most radiant beauty... this knowledge, this feeling is at the center of true religiousness.
If I give you a pfennig, you will be one pfennig richer and I'll be one pfennig poorer. But if I give you an idea, you will have a new idea, but I shall still have it too.
In matters of truth and justice, there is no difference between large and small problems, for issues concerning the treatment of people are all the same.
The belief in an external world independent of the perceiving subject is the basis of all natural science. Since, however, sense perception only gives information of this external world or of "physical reality" indirectly, we can only grasp the latter by speculative means. It follows from this that our notions of physical reality can never be final. We must always be ready to change these notions - that is to say, the axiomatic basis of physics - in order to do justice to perceived facts in the most perfect way.
No one must think that Newton’s great creation can be overthrown in any real sense by this [Theory of Relativity] or by any other theory. His clear and wide ideas will for ever retain their significance as the foundation on which our modern conceptions of physics have been built.
No fairer destiny could be allotted to any physical theory than that it should of itself point out the way to the introduction of a more comprehensive theory, in which it lives on as a limiting case.
If I am right the Germans will say I was a German, and the French will say I was a Jew; If I am wrong the Germans will say I was a Jew and the French will say I was a German.
The Constitution only guarantees the American people the right to pursue happiness. You have to catch it yourself. A table, a chair, a bowl of fruit and a violin; what else does a man need to be happy?