Thinking is hard work; that's why so few do it.
My scientific work is motivated by an irresistible longing to understand the secrets of nature and by no other feeling. My love for justice and striving to contribute towards the improvement of human conditions are quite independent from my scientific interests.
My internal and external life depend so much on the work of others that I must make an extreme effort to give as much as I receive.
Why does this magnificent applied science which saves work and makes life easier bring us so little happiness? ... The simple answer runs: 'Because we have not yet learned to make sensible use of it.'
Genius is 1% talent and 99% percent hard work...
I never allow myself to become discouraged under any circumstances. The three great essentials to achieve anything worthwhile are first, hard work, second, stick-to-ittiveness, third, common sense.