Neo-Pythagorean

Neopythagoreanism (or Neo-Pythagoreanism) was a school of Hellenistic philosophy which revived Pythagorean doctrines. Neopythagoreanism was influenced by Middle Platonism and in turn influenced Neoplatonism. It originated in the 1st century BCE and flourished during the 1st and 2nd centuries CE. The 1911 Britannica describes Neopythagoreanism as "a link in the chain between the old and the new" within Hellenistic philosophy. As such, it contributed to the doctrine of monotheism as it emerged during Late Antiquity (among other things influencing early Christianity). Central to Neopythagorean thought was the concept of a soul and its inherent desire for a unio mystica with the divine.

The word "Neopythagoreanism" is a modern (19th century) term, coined as a parallel of "Neoplatonism".

In the 1st century BCE Cicero's friend Nigidius Figulus made an attempt to revive Pythagorean doctrines, but the most important members of the school were Apollonius of Tyana and Moderatus of Gades in the 1st century CE. Other important Neopythagoreans include the mathematician Nicomachus of Gerasa (fl. 150 CE), who wrote about the mystical properties of numbers. In the 2nd century, Numenius of Apamea sought to fuse additional elements of Platonism into Neopythagoreanism, prefiguring the rise of Neoplatonism. (Iamblichus, in particular, was especially influenced by Neopythagoreanism).

Neopythagoreanism was an attempt to re-introduce a mystical religious element into Hellenistic philosophy (dominated by the Stoics) in place of what had come to be regarded as an arid formalism. The founders of the school sought to invest their doctrines with the halo of tradition by ascribing them to Pythagoras and Plato. They went back to the later period of Plato's thought, the period when Plato endeavoured to combine his doctrine of Ideas with Pythagorean number theory, and identified the Good with the Monad (which would give rise to the Neoplatonic concept of the One), the source of the duality of the Infinite and the Measured with the resultant scale of realities from the One down to the objects of the material world.

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