Principles of Non-Philosophy is a treatise on the method, axioms and objectives of non-philosophy and represents François Laruelle's mature philosophy. As well as presenting the method and principles of non-philosophy, it includes a history of the development of non-philosophy, a novel conception of science, a discussion of non-philosophical causality and new theories of the subject and object of thought. Providing an introduction to Laruelle's novel theory of 'non-epistemology' or 'unified theory of thought', this volumes challenges the way we think about the traditional philosophical problems. Now available in paperback, this edition brings together all the elements of Laruelle's thought developed over twenty years and laying the foundations for his later work; Principles of Non-Philosophy is arguably his magnum opus. I am delighted to see the appearance of this English translation of Principles of Non-Philosophy, one of Laruelle's major works. The project is formidable: nothing less than "non-philosophy"-as in "non-Euclidean"- which is not the simple lack or absence of philosophy, nor what philosophy has marginalized, nor anti-philosophy, nor meta-philosophy, nor the end or death of philosophy. What's left? A withdrawal or suspension of the authority of philosophy in order to undertake a new practice of philosophy more "rigorous" than philosophy, to think not "about" but "from out of" and "according to" the non-objectifiable experience of what Laruelle calls radical immanence, the One, or the Real. It sounds at times not unlike Heidegger's idea that there is something to be thought in metaphysics to which metaphysics has no access. Our thanks to translators Nicola Rubczak and Anthony Paul Smith for their considerable labor in making the important work of this daring if daunting thinker accessible to Anglophone readers.