Idealist notions took a strong hold among physicists of the early 20th century confronted with the paradoxes of quantum physics and the theory of relativity. In The Grammar of Science, Preface to the 2nd Edition, 1900, Karl Pearson wrote, "There are many signs that a sound idealism is surely replacing, as a basis for natural philosophy, the crude materialism of the older physicists." This book influenced Einstein's regard for the importance of the observer in scientific measurements[citation needed]. In § 5 of that book, Pearson asserted that "...science is in reality a classification and analysis of the contents of the mind...." Also, "...the field of science is much more consciousness than an external world." COUNT 5
QSN1 Among what twentieth century scientists was idealism popular? ANS1 physicists QSN2 Along with quantum physics generally, what scientific doctrine caused some physicists to embrace idealism? ANS2 relativity QSN3 In what year was the second edition of The Grammar of Science published? ANS3 1900 QSN4 What did Pearson claim that science classifies? ANS4 contents of the mind QSN5 Who is claimed to have been influenced by The Grammar of Science? ANS5 Einstein