By this reminder Eddington shows how far science has reconciled itself to the philosophic scepticism at which man’s thinking had arrived in the days of Hume. In so far as the above remark was intended to be a consolation for the bewildered student, it is poor comfort in the light of the actions which science has let loose with the help of those unknown entities. For it is just this resignation of human thought which renders it unable to cope with the flood of phenomena springing from the sub-material realm of nature, and has allowed scientific research to outrun scientific understanding.