One of the simplest and most effective techniques to learn something is to try to teach it.

— Andy Hunt, Pragmatic Thinking and Learning

The detailed blow-by-blow flow chart, however, is an obsolete nuisance, suitable only for initiating beginners into algorithmic thinking.

— Frederick P. Brooks Jr., The Mythical Man-Month

T. S. Eliot, a great admirer of the work, commented: “How much the work of logicians has done to make of English a language in which it is possible to think clearly and exactly on any subject. The Principia Mathematica are perhaps a greater contribution to our language than they are to mathematics.”

— Chris Bernhardt, Turing’s Vision

…there is no way that Newton’s law—or any other law of physics—can be proved in the mathematical sense of the word.

— Eli Maor, E

What is defeat? Nothing but education; nothing but the first steps to something better. —WENDELL PHILLIPS…

— Ryan Holiday, The Obstacle Is the Way