Among technical books, books by Cornelius Lanczos are some of the best (less popular) books I've read. Some quotes from his "The Variational Principles of Mech

Among technical books, books by Cornelius Lanczos are some of the best (less popular) books I've read. Some quotes from his "The Variational Principles of Mechanics": From the Preface: Many of the scientific treatises of today are formulated in a half-mystical language, as though to impress the reader with the uncomfortable feeling that he is in the permanent presence of a superman. The present book is conceived in a humble spirit and is written for humble people. From Chapter 8: Put off thy shoes from off thy feet, for the place whereon thou standest is holy ground. -- EXODUS III, 5 We have done considerable mountain climbing. Now we are in the rarefied atmosphere of theories of excessive beauty and we are nearing a high plateau on which geometry, optics, mechanics, and wave mechanics meet on common ground. Only concentrated thinking, and a considerable amount of recreation, will reveal the full beauty of our subject in which the last word has not yet been spoken. This book was also on Gerald Jay Sussman's must-read list of books [1]. Another great book of his is "Linear Differential Operators" -- if you've ever wanted an intuitive explanation for why d/dx is not Hermitian but d^2/dx^2 is, this is the book you need to read. A quote from the book that resonated with me when I first read it: Since the days of antiquity it has been the privilege of the mathematician to engrave his conclusions, expressed in a rarefied and esoteric language, upon the rocks of eternity. While this method is excellent for the codification of mathematical results, it is not so acceptable to the many addicts of mathematics, for whom the science of mathematics is not a logical game, but the language in which the physical universe speaks to us, and whose mastery is inevitable for the comprehension of natural phenomena. [1]: http://aurellem.org/thoughts/html/sussman-reading-list.html http://aurellem.org/thoughts/html/sussman-reading-list.html