Ye great teachers: listen to what you say!

Insofar as he makes use of his healthy senses, man himself is the best and most exact scientific instrument possible. The greatest misfortune of modern physics is that its experiments have been set apart from man, as it were, physics refuses to recognize nature in anything not shown by artificial instruments, and even uses this as a measure of its accomplishments.

What right those who govern have to govern they don't question, they just govern. Whether the people have a right to depose them that doesn't concern them. All they are concerned with is that the people will not be tempted to depose them.

Solitude is fine when you are at peace with yourself and have something definite to do.

The force of a language does not consist of rejecting what is foreign but of swallowing it.

The field of experience is the whole universe in all directions. Theory remains shut up within the limits of human faculties.

Man believes himself always greater than he is, and is esteemed less than he is worth.