This original collection of essays by some of the best world specialists of ancient Greek philosophy focuses on the philosophical texts written during the Hellenistic and Imperial times under the names of Pythagoras and the Pythagoreans. Their unknown authors claimed to convey the positions of the pristine Pythagorean School on metaphysics, theology, number philosophy, physics, logic, political philosophy, ethics, and the proper way to live. The most audacious among them presented themselves as the sources from which Plato and Aristotle drew inspiration for the Timaeus and the Categories, and they were considered authoritative by most ancient thinkers, thus leading to a renaissance of the Platonic and Pythagorean tradition.