David Armstrong is one of the main architects of the current renaissance in metaphysics, so it is very useful to have a concise summary of his latest views... As one might expect, it is a model of clarity and rich in ideas. It certainly satisfies the description "systematic" that appears in its title. Without sacrificing rigour, he has succeeded in making it as accessible as possible to as wide a philosophical audience as possible... it is a pleasure, as always, to wrestle with the deep philosophical questions that Armstrong continues to present us with so vivaciously.
E. J. Lowe, Notre Dame Philosophical Reviews