The oldest, shortest words- 'yes' and 'no'- are those which require the most thought.
To live is not merely to breathe; it is to act; it is to make use of our organs, senses, faculties - of all those parts of ourselves which give us the feeling of existence
Admiration is the daughter of ignorance.
To kill an error is as good a service as, and sometimes even better than, the establishing of a new truth or fact
It is man that makes truth great, not truth that makes man great.
Beauty is not in the face; beauty is a light in the heart.
Courage, above all things, is the first quality of a warrior.
The first thing you'll have to do, is the last thing you wished.
There is geometry in the humming of the strings. There is music in the spacing of the spheres.
He who can destroy a thing, can control a thing.
You can be rich in spirit, kindness, love and all those things that you can't put a dollar sign on.
We seldom realize, for example that our most private thoughts and emotions are not actually our own. For we think in terms of languages and images which we did not invent, but which were given to us by our society.
Time flies over us, but leaves its shadow behind.
Everything we hear is an opinion, not a fact. Everything we see is a perspective, not the truth.
The first method for estimating the intelligence of a ruler is to look at the men he has around him.
It takes a great deal of bravery to stand up to our enemies, but just as much to stand up to our friends.
Don't criticize what you don't understand, son. You never walked in that man's shoes.
Each problem that I solved became a rule which served afterwards to solve other problems.
Thoughts without content are empty, intuitions without concepts are blind.
The cure for pain is in the pain.
Real knowledge is to know the extent of one's ignorance.