Mysticism and Logic and Other Essays

The First 1000 Euler Numbers

Complete Works of Plutarch — Volume 3: Essays and Miscellanies

The Harvard Classics Volume 38 Scientific Papers (Physiology, Medicine, Surgery, Geology)

Filosofía Fundamental, Tomo I

Science and Morals and Other Essays

The Evanston Colloquium: Lectures on Mathematics Delivered From Aug. 28 to Sept. 9, 1893 Before Members of the Congress of Mathematics Held in Connection with the World's Fair in Chicago

The reason why

The Old Humanities and the New Science

All Things are Possible

Icarus

Philosophy