This now-classic work challenges what Ryle calls philosophy's "official theory, " the Cartesian "myth" of the separation of mind and matter. Ryle's linguistic analysis remaps the conceptual geography of mind, not so much solving traditional philosophical problams as dissolving them into the mere consequences of misguided language. His plain language and essentially simple purpose put him in the tradition of Locke, Berkeley, Mill, and Russell - philisophers whose best work, like Ryle's, has become a part of our general literature.