them is this: This term was applied to things of higher value, in order that what is more excellent might be distinguished, if not by a definition of nature answering to the literal meaning of [Greek: huphistasthai]=_substare_, at any rate by the words [Greek: hupostasis]=_substantia_. To begin with, then, man is essence, i.e. [Greek: ousia], subsistence, i.e. [Greek: ousiosis, hupostasis], i.e. substance, [Greek: prosopon], i.e. person: [Greek: ousia] or _essentia_ because he is, [Greek: ousiosis], or subsistence because he is not accidental to any subject, [Greek: hupostusis] or substance because he is subject to all the things which are not subsistences or [Greek: ousioseis], while he is [Greek: prosopon] or person because he is a rational individual. Next, God is [Greek: ousia], or essence, for He is and is especially that from which proceeds the Being of all things. To Him belong [Greek: ousiosis], i.e. subsistence, for He subsists in absolute independence, and [Greek: huphistasthai], for He is substantial Being. Whence we go on to say that there is one [Greek: ousia] or [Greek: ousiosis], i.e. one essence or subsistence of the Godhead, but three [Greek: hupostaseis] or substances. And indeed, following this use, men have spoken of One essence, three substances and three persons of the Godhead. For did not the language of the Church forbid us to say three substances in speaking of God,[63] substance might seem a right term to apply to Him, not because He underlies all other things like a substrate, but because, just as He excels above all things, so He is the foundation and support of things, supplying them all with [Greek: ousiosthai] or subsistence. [60] Boethius's definition of _persona_ was adopted by St. Thomas (S. i. 29. 1), was regarded as classical by the Schoolmen, and has the approval of modern theologians. Cf. Dorner, _Doctrine of Christ_, iii. p. 311. [61] Implying a short penultimate. [62] _Tusc._ ii. 15. 35. [63] For a similar submission of his own opinion to the usage of the Church cf. the end of _Tr._ i. and of _Tr._ ii. IV.