Overpopulation in various countries has become a serious threat to the health of people and a grave obstacle to any attempt to organise peace on this planet
A man's moral worth is not measured by what his religious beliefs are but rather by what emotional impulses he has received from Nature during his lifetime.
Our world faces a crisis as yet unperceived by those possessing power to make great decisions for good or evil. The unleashed power of the atom has changed everything save our modes of thinking and we thus drift toward unparalleled catastrophe.
Out yonder there is this huge world, which exists independently of us human beings and which stands before us like a great, eternal riddle, at least partially accessible to our inspection and thinking
Every day, man is making bigger and better fool-proof things, and every day, nature is making bigger and better fools. So far, I think nature is winning.
It is quite clear to me that the religious paradise of youth, which [I] lost, was a first attempt to free myself from the chains of the 'merely personal,' from an existence which is dominated by wishes, hopes, and primitive feelings.
What a person thinks on his own without being stimulated by the thoughts and experiences of the other people is even in the best case rather paltry and monotonous.