Editing Theory of categories (section)

===Plotinus===
[[Plotinus]] in writing his ''[[Enneads]]'' around AD 250 recorded that "Philosophy at a very early age investigated the number and character of the existents&nbsp;... some found ten, others less&nbsp;... to some the genera were the first principles, to others only a generic classification of existents."<ref>''Op.cit.9'' VI.1.1</ref> He realised that some categories were reducible to others saying "Why are not Beauty, Goodness and the virtues, Knowledge and Intelligence included among the primary genera?"<ref>''Ibid.'' VI.2.17</ref> He concluded that such [[Transcendentals|transcendental categories]] and even the [[Categories (Aristotle)|categories of Aristotle]] were in some way posterior to the three [[Eleatics|Eleatic]] categories first recorded in Plato's dialogue ''[[Parmenides (dialogue)|Parmenides]]'' and which comprised the following three coupled terms: 
*Unity/Plurality
*Motion/Stability
*Identity/Difference<ref>Plato ''Parmenides'' (tr. Jowett B., ''The Dialogues of Plato'', Clarendon Press, Oxford, 1875) p.162</ref>

[[Plotinus]] called these "the hearth of reality"<ref>''Op.cit.9'' Op.cit.1.4</ref> deriving from them not only the three categories of Quantity, Motion and Quality but also what came to be known as "the three moments of the [[Neoplatonism|Neoplatonic world process]]":
*First, there existed the "One", and his view that "the origin of things is a contemplation"
*The Second "is certainly an activity&nbsp;... a secondary phase&nbsp;... life streaming from life&nbsp;... energy running through the universe"
*The Third is some kind of Intelligence concerning which he wrote "Activity is prior to Intellection&nbsp;... and self knowledge"<ref>''Ibid.'' III.8.5</ref>

Plotinus likened the three to the centre, the radii and the circumference of a circle, and clearly thought that the principles underlying the categories were the first principles of creation. "From a single root all being multiplies." Similar ideas were to be introduced into Early Christian thought by, for example, [[Gregory of Nazianzus]] who summed it up saying "Therefore, Unity, having from all eternity arrived by motion at duality, came to rest in [[Trinity]]."<ref>Rawlinson A.E. (ed.) ''Essays on the Trinity and the Incarnation'' (Longmans, London, 1928) pp.241-244</ref>