This title was first published in 2000. Philosophers have been greatly concerned with the nature of explanation, but no account has been fully satisfactory within science or plausible in the wider world. The author asserts that this is due to a misplaced focus and that instead of focusing on explanation, philosophers should consider understanding. This work outlines his theory and defends it against some objections. Attempts to understand understanding can become self-referential, but the book is intended to enable readers to build a good mental model of the author's theory.