Aristotle's Posterior Analytics, Clarendon Aristotle Series, isone of the most important books, yet, I think one of the mostoverlooked, in philosophy. Even a brief reading of the book will show that much of what it contains was adopted by Heidegger, Hegel, Marx and others. The simplicity of Aristotle's Posterior Analytics is misleading. It took Heidegger to show its true importance. Key topics of the book discuss definition, dialectics and purpose. It is astonishing to see that the complicated works of major philosophical figures like Heidegger and Hegel were first born in the clearly written thought of Aristotle.