He was distinguished for ignorance; for he had only one idea, and that was wrong.
The secret to success is constancy of purpose.
Silence is the mother of truth.
You asked me where I generally lived. In my workshop [i.e. in his study] in the mornings and always in the library in the evening. Books are companions even if you don't open them.
Nothing can resist the human will that will stake even its existence on its stated purpose.
There is no waste of time in life like that of making explanations.