Be wary of passing the judgment: obscure. To find something obscure poses no difficult, elephants and poodles find many things obscure.

I ceased in the year 1764 to believe that one can convince one’s opponents with arguments printed in books. It is not to do that, therefore, that I have taken up my pen, but merely so as to annoy them, and to bestow strength and courage on those on our own side, and to make it known to the others that they have not convinced us.

The most heated defenders of a science, who cannot endure the slightest sneer at it, are commonly those who have not made very much progress in it and are secretly aware of this defect.

The worst thing you can possibly do is worrying and thinking about what you could have done.

Everyone is a genius at least once a year. The real geniuses simply have their bright ideas closer together.

How might letters be most efficiently copied so that the blind might read them with their fingers?

If another Messiah was born he could hardly do so much good as the printing-press.