THREE:How far Plotinus was indebted to Ammonius Saccas for his speculative ideas is another question with respect to which the Pythagoreanising tendencies of his biographer may282 possibly have contributed to the diffusion of a serious misconception. What Porphyry tells us is this. Before leaving Alexandria, Plotinus had bound himself by a mutual agreement with two of his fellow-pupils, Herennius and Origines (not the Christian Father, but a pagan philosopher of the same age and name), to keep secret what they had learned by listening to the lectures of Ammonius. Herennius, however, soon broke the compact, and Origines followed his example. Plotinus then considered that the engagement was at an end, and used the results of his studies under Ammonius as the basis of his conversational lectures in Rome, the substance of which, we are left to suppose, was subsequently embodied in his published writings. But, as Zeller has pointed out, this whole story bears a suspicious resemblance to what is related of the early Pythagorean school. There also the doctrines of the master were regarded by his disciples as a mystery which they pledged themselves to keep secret, and were only divulged through the infidelity of one among their number, Philolaus. And the same critic proves by a careful examination of what are known to have been the opinions of Origines and Longinus, both fellow-pupils of Plotinus, that they differed from him on some points of essential importance to his system. We cannot, therefore, suppose that these points were included in the teaching of their common master, Ammonius.425 But if this be so, it follows that Plotinus was the real founder of the Neo-Platonic school; and, in all cases, his writings remain the great source whence our knowledge of its first principles is derived.[161]
