Distinguer pour unir, ou Les degres du savoir was first published in 1932 by Jacques Maritain. In this new translation of The Degrees of Knowledge, Ralph McInerny attempts a more careful expression of Maritain's original masterpiece than previous translations. Maritain proposes a hierarchy of the forms of knowledge by discussing the degrees of rational and suprarational understanding. Nine appendices, some longer than the chapters of the book, advance Maritain's thought, often by taking on criticism of earlier editions of the work. Rightly called Maritain's cardinal work, The Degrees of Knowledge is a magnificent and sagacious achievement.