Leonard Peikoff discusses the nature of principles and why moral principles are necessary. He explains man’s need for a long-range perspective that takes into account all of his actions across his entire lifespan, and then argues that such a perspective is possible only by means of the unit-reducing power of man’s conceptual faculty. Peikoff illustrates these points by discussing the virtues of honesty and rationality, showing why these are principles which must be held as absolutes.