The philosophical and mathematical commentaries of Proclus on the first book of Euclid's elements (Vol. 1 of 2) : $b To which are added, A history of the restoration of Platonic theology, by the latter Platonists: And a translation from the Greek of Proclus's Theological elements
Plato · en
If such then were the lives of the men who brought this contemplative
science to its present perfection, and who are to this day our masters
in geometry; if such were the exalted sentiments they entertained
of its dignity and worth, what greater proof can we require of its
being valuable for its own sake, and as subservient to the energies
of intellect? We have ample evidence too, of its being degraded
when brought down to the common purposes of life, in the example
of those who, with this view, have disguised it with the dark and
sordid involutions of algebraic calculation; for it was solely to
facilitate practice, that this barbarous invasion has been admitted by
the moderns. Let me then be permitted to persuade the few who study
geometry in its ancient purity, and who consider the ruins of Grecian
literature on this, as well as on every other science, the models
of perfection, to enter with avidity on the study of the ensuing
Commentaries, and endeavour to fathom the depth of our profound and
elegant philosopher: for by this means they may happily obtain the end
of all true science, the purification of the soul; and be able to draw
the light of perfect wisdom, from the undecaying and inexhaustible
fountain of good.
But if it should be asked in what these energies of intellect
consist, to which all science ultimately refers? I answer, in the
contemplation of true being, or those ideal and divine forms, with
which the intelligible world is replete. Now this great end is not
to be accomplished without previous discipline, a long exercise of
the reasoning power, and a continued series of philosophic endurance.
For this end, when attained, is no other than the enjoyment of that
felicity congenial to the soul previous to her immersion in body. But,
for the further information of the liberal reader on this important
subject, the following paraphrases from Porphyry and Proclus are
subjoined; the former instructing us in the various purifications
necessary to this end; and the latter exhibiting the gradations by
which we may rise to the speculation of reality, and (leaving all
_multitude_ behind) ascend to the divinely solitary principle of
things, the ineffable _One_.