The Dyad is a title used by the Pythagoreans for the number two, representing the principle of "twoness" or "otherness".
Numenius of Apamea, a Neopythagorean philosopher in the latter 2nd century CE, said that Pythagoras gave the name of Monad to God, and the name of Dyad to matter. [1] [2] Aristotle equated matter as the formation of the elements (energies) into the material world as the static material was formed by the energies being acted upon by force or motion.[ citation needed ] Later Neoplatonic Philosophers and idealists like Plotinus treated the dyad as a second cause (demiurge),[ citation needed ] which was the divine mind (nous) that via a reflective nature[ clarification needed ] (finiteness) causes matter to "appear" or become perceivable.