The traditional religions worry me. Their long history proves that they have not understood the meaning of the commandment: Thou shalt not kill. If we want to save this world from unimaginable destruction we should concentrate not on the faraway God , but on the heart of the individual.
A theory is the more impressive the greater is the simplicity of its premises, the more different are the kinds of things it relates and the more extended the range of its applicability.
The scientific theorist is not to be envied. For Nature, or more precisely experiment, is an exorable and not very friendly judge of his work. It never says "yes" to a theory. In the most favorable cases it says "Maybe," and in the great majority of cases simply "No." If an experiment agrees with a theory it means for the latter "Maybe," and if it does not agree it means "No." Probably every theory will some day experience its "No" - most theories, soon after conception.
From a certain temperature on, the molecules 'condense' without attractive forces; that is, they accumulate at zero velocity. The theory is pretty, but is there some truth in it.
I have come to know the mutability of all human relationships and have learned to insulate myself against both heat and cold so that a temperature balance is fairly well assured.
Scientific greatness is less a matter of intelligence than character; if the scientist refuses to compromise or accept incomplete answers and persists in grappling the most basic and difficult questions.
Long hair minimizes the need for barbers; socks can be done without; one leather jacket solves the coat problem for many years; suspenders are superfluous.