"This is an admirable book. Anjum and Mumford advance a novel philosophical thesis, they defend it with rigour and ingenuity and explore uncharted territories. Given that the map of the area is currently being drawn there are bound to be inaccuracies and infelicities. But that's the fate of all explorers, philosophical or otherwise. Despite our critical points, Anjum and Mumford have succeeded in producing a thorough, deep and challenging exploration of these metaphysical matters." - Stathis Psillos and Stavros Ioannidis, Notre Dame Philosophical Reviews