Albert Einstein described Relativity as a “popular explosion” of his famous theory. Written in 1916, it introduced the lay audience to the remarkable perspective which had overturned theoretical physics. Einstein’s genius was to express this perspective in understandable terms.

“The present book is intended,” Einstein wrote in 1916, “as far as possible, to give an exact insight into the Theory of Relativity to those readers who, from a general scientific and philosophical point of view, are interested in the theory, but who are not conversant with the mathematical apparatus of theoretical physics. . . . In the interest of clearness, it appeared to me inevitable that I should repeat myself frequently, without paying the slightest attention to the elegance of the presentation. I adhered scrupulously to the precept of that brilliant theoretical physicist L. Boltzmann, according to whom matters of elegance ought to be left to the tailor and to the cobbler.”