"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."

Originally published: New York : H. Holt, 1920.

Pt. I.Special Theory of Relativity -- 1. Physical Meaning of Geometrical Propositions -- 2. System of Co-ordinates -- 3. Space and Time in Classical Mechanics -- 4. Galileian System of Co-ordinates -- 5. Principle of Relativity (in the Restricted Sense) -- 6. Theorem of the Addition of Velocities Employed in Classical Mechanics -- 7. Apparent Incompatibility of the Law of Propagation of Light with the Principle of Relativity -- 8. On the Idea of Time in Physics -- 9. Relativity of Simultaneity -- 10. On the Relativity of the Conception of Distance -- 11. Lorentz Transformation -- 12. Behaviour of Measuring-Rods and Clocks in Motion -- 13. Theorem of the Addition of Velocities. The Experiment of Fizeau -- 14. Heuristic Value of the Theory of Relativity -- 15. General Results of the Theory -- 16. Experience and the Special Theory of Relativity -- 17. Minkowski's Four-dimensional Space. Pt. 2. General Theory of Relativity -- 18. Special and General Principle of Relativity -- 19. Gravitational Field -- 20. Equality of Inertial and Gravitational Mass as an Argument for the General Postulate of Relativity -- 21. In what Respects are the Foundations of Classical Mechanics and of the Special Theory of Relativity Unsatisfactory? -- 22. Few Inferences from the General Principle of Relativity -- 23. Behaviour of Clocks and Measuring-Rods on a Rotating Body of Reference -- 24. Euclidean and non-Euclidean Continuum -- 25. Gaussian Co-ordinates -- 26. Space-Time Continuum of the Special Theory of Relativity Considered as a Euclidean Continuum -- 27. Space-Time Continuum of the General Theory of Relativity is not a Euclidean Continuum -- 28. Exact Formulation of the General Principle of Relativity -- 29. Solution of the Problem of Gravitation on the Basis of the General Principle of Relativity -- Pt. III. Considerations on the Universe as a Whole. Pt. III. Considerations on the Universe as a Whole -- Cosmological Difficulties of Newton's Theory -- 31. Possibility to a "Finite" and yet "Unbounded" Universe -- 32. Structure of Space according to the General Theory of Relativity. -- App. 1. Simple Derivation of the Lorentz Transformation [Supplementary to Section 11] -- App. 2. Minkowski's Four-dimensional Space ("World") [Supplementary to Section 17] -- App. 3. Experimental Confirmation of the General Theory of Relativity -- App. 4. Structure of Space according to the General Theory of Relativity [Supplementary to Section 32] -- App. 5. Relativity and the Problem of Space.