from Plotinus' Sixth Ennead,
* Tractate 9, 7-11, Translated by Stephen Mackenna and B. S. Page
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Is then this "centre" of our souls the Principle for which we are seeking?
We must look yet further: we must admit a Principle in which all these centres coincide: it will be a centre by analogy with the centre of the circle we know. The soul is not a circle in the sense of the geometric figure but in that it at once contains the Primal Nature [as centre] and is contained by it [as circumference], that it owes its origin to such a centre and still more that the soul, uncontaminated, is a self-contained entity.
Τὸ οὖν τῆς ψυχῆς οἷον κέντρον τοῦτό ἐστι τὸ ζητούμενον;
῍Η ἄλλο τι δεῖ νομίσαι͵ εἰς ὃ πάντα οἷον κέντρα συμπίπτει; Καὶ ὅτι ἀναλογίᾳ τὸ κέντρον τοῦδε τοῦ κύκλου; Οὐδὲ γὰρ οὕτω κύκλος ἡ ψυχὴ ὡς τὸ σχῆμα͵ ἀλλ΄ ὅτι ἐν αὐτῇ καὶ περὶ αὐτὴν ἡ ἀρχαία φύσις͵ καὶ ὅτι ἀπὸ τοιούτου͵ καὶ ἔτι μᾶλλον καὶ ὅτι χωρισθεῖσαι ὅλαι.
Plotinus, The Enneads / Full Text in English
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