Defending his controversial Theory of Relativity, Albert Einstein delivered a series of lectures at Princeton in 1921, expanding on them the following year in the book The Meaning of Relativity. Reprinting these seminal scientific texts in their entirety, Hanoch Gutfreund and Jürgen Renn also provide fresh, original perspectives, placing Einstein's achievements into a broader context and clarifying the basic concepts. Also included in this admirably thorough historical overview are photographs, selections from Einstein's correspondence, and capsule biographies of the many scientists caught up in the debate.

"A lucid, readable, and deeply informed account of Einstein's development of relativity theory."—Walter Isaacson