One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled wit… - Bertrand Russell

All exact science is dominated by the idea of approximation. When a man tells you that he knows the exact truth about anything, you are safe in inferring that he is an inexact man.

... it may be hoped that the white population of the world will soon cease to increase. The Asiatic races will be longer, and the negroes still longer, before their birth rate falls sufficiently to make their numbers stable without help of war and pestilence. But it is to be hoped that the religious prejudices which have hitherto hampered the spread of birth control will die out, and that ... the whole world will learn not to be unduly prolific. Until that happens, the benefits aimed at by socialism can only be partially realized, and the less prolific races will have to defend themselves against the more prolific by methods which are disgusting even if they are necessary.

Both in thought and in feeling, even though time be real, to realise the unimportance of time is the gate of wisdom.