Dr. Albert Einstein,
Originator of the Special and General Theories of Relativity
SCIENTIFIC AMERICAN PUBLISHING CO.,
MUNN & CO.
1921
Copyright 1921
by
Scientific American Publishing Company
All rights reserved
Great Britain copyright secured
The right of translation is reserved in all languages, including the Scandinavian
Swedish rights secured by Thall and Carlsson, Stockholm[iii]
PREFACE
The obstacles which the layman finds to understanding Einstein’s relativity theorieslie not so much in the inherent difficulty of these theories themselves as in thedifficulty of preparing the mind for their reception. The theory is no more difficultthan any scientific development of comparable depth; it is not so difficult as someof these. But it is a fact that for a decent understanding of it, a large backgroundof scientific knowledge and scientific habit of thought is essential. The bulk ofthe writers who have attempted to explain Einstein to the general reader have notrealized the great gulf which lies between the mental processes of the trained mathematicianand those of the man in the street. They have not perceived that the lay reader mustbe personally conducted for a long distance from the vestibule of the temple of sciencebefore he comes to Einstein, and that he cannot by any possibility make this journeyunaided. The result has been to pitchfork the reader into the intricacies of the subjectwithout adequate preparation.
The present volume avoids this mistake with the utmost care. I