The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. What I Believe. The bitter and the sweet come from the outside, the hard from within, from one's own efforts. Out of My Later Years.
Common sense is the collection of prejudices acquired by age eighteen.
Quoted in E T Bell Mathematics, Queen and Servant of the Sciences. 1952. God does not care about our mathematical difficulties. He integrates empirically. Quoted in L Infeld Quest, 1942. Nature to him was an open book, whose letters he could read without effort.