But nature did not deem it her business to make the discovery of her laws easy for us.

The theory must not contradict empirical facts.

Isn't it strange that I who have written only unpopular books should be such a popular fellow?

Only the Catholic Church protested against the Hitlerian onslaught on liberty. Up till then I had not been interested in the Church, but today I feel a great admiration for the Church, which alone has had the courage to struggle for spiritual truth and moral liberty

It must be conceded that a theory has an important advantage if its basic concepts and fundamental hypotheses are 'close to experience,' and greater confidence in such a theory is certainly justified. There is less danger of going completely astray, particularly since it takes so much less time and effort to disprove such theories by experience. Yet more and more, as the depth of our knowledge increases, we must give up this advantage in our quest for logical simplicity in the foundations of physical theory.

I am satisfied with the mystery of the eternity of life.

In the view of such harmony in the cosmos which I, with my limited human mind, am able to recognize, there are yet people who says there is no God. But what makes me really angry is that they quote me for support of such views. (The Expanded Quotable Einstein, Princeton University, page 214)