Principium motuum voluntariorum est bonum in communi, in quod voluntas naturaliter tendit, sicut etiam quaelibet potentia in suum obiectum (et etiam ipse finis ultimus, qui hoc modo se habet in appetibilibus, sicut prima principia demonstrationum in intelligibilibus, et universaliter omnia illa quae conveniunt volenti secundum suam naturam), quia non per voluntatem appetimus solum ea quae pertinent ad potentiam voluntatis, sed etiam ea quae pertinent ad singulas potentias, et ad totum hominem.
The principle of voluntary movements is good in general, to which the will tends naturally, as does each power to its object (and again it is the last end, which stands in the same relation to things appetible, as the first principles of demonstrations to things intelligible and, speaking generally, it is all those things which belong to the willer according to his nature), because it is not only things pertaining to the will that the will desires, but also that which pertains to each power, and to the entire man.
Unde naturaliter homo vult non solum obiectum voluntatis, sed etiam alia quae conveniunt aliis potentiis, ut cognitionem veri, quae convenit intellectui; et esse et vivere et alia huiusmodi, quae respiciunt consistentiam naturalem; quae omnia comprehenduntur sub obiecto voluntatis, sicut quadam particularia bona.
Wherefore man wills naturally not only the object of the will, but also other things that are appropriate to the other powers; such as the knowledge of truth, which befits the intellect; and to be and to live and other like things which regard the natural well-being; all of which are included in the object of the will, as so many particular goods.
Cum igitur voluntas sit quaedam vis immaterialis sicut et intellectus, respondet sibi naturaliter aliquod unum commune, scilicet bonum, sicut etiam intellectui aliquod unum commune, scilicet verum, vel ens, vel quod quid est. Sub bono autem communi multa particularia bona continentur, ad quorum nullum voluntas determinatur.
Since, therefore, the will is an immaterial power like the intellect, some one general thing corresponds to it naturally, which is the good; just as to the intellect there corresponds some one general thing, which is the true, or being, or "what a thing is." And under good in general are included many particular goods, to none of which is the will determined.
Sicut Boetius dicit in libro de duabus naturis, et philosophus in V Metaphys., natura dicitur multipliciter. Quandoque enim dicitur principium intrinsecum in rebus mobilibus. Et talis natura est vel materia, vel forma materialis, ut patet ex II Physic. Alio modo dicitur natura quaelibet substantia, vel etiam quodlibet ens. Et secundum hoc, illud dicitur esse naturale rei, quod convenit ei secundum suam substantiam. Et hoc est quod per se inest rei. In omnibus autem, ea quae non per se insunt, reducuntur in aliquid quod per se inest, sicut in principium. Et ideo necesse est quod, hoc modo accipiendo naturam, semper principium in his quae conveniunt rei, sit naturale. Et hoc manifeste apparet in intellectu, nam principia intellectualis cognitionis sunt naturaliter nota. Similiter etiam principium motuum voluntariorum oportet esse aliquid naturaliter volitum.
As Boethius says (De Duabus Nat.) and the Philosopher also (Metaph. v, 4) the word "nature" is used in a manifold sense. For sometimes it stands for the intrinsic principle in movable things. In this sense nature is either matter or the material form, as stated in Phys. ii, 1. In another sense nature stands for any substance, or even for any being. And in this sense, that is said to be natural to a thing which befits it in respect of its substance. And this is that which of itself is in a thing. Now all things that do not of themselves belong to the thing in which they are, are reduced to something which belongs of itself to that thing, as to their principle. Wherefore, taking nature in this sense, it is necessary that the principle of whatever belongs to a thing, be a natural principle. This is evident in regard to the intellect: for the principles of intellectual knowledge are naturally known. In like manner the principle of voluntary movements must be something naturally willed.
In rebus naturalibus id quod est naturale quasi consequens formam tantum, semper actu inest, sicut calidum igni. Quod autem est naturale sicut consequens materiam, non semper actu inest, sed quandoque secundum potentiam tantum. Nam forma est actus, materia vero potentia.
In the case of natural things, that which is natural, as a result of the form only, is always in them actually, as heat is in fire. But that which is natural as a result of matter, is not always in them actually, but sometimes only in potentiality: because form is act, whereas matter is potentiality.
Et similiter non oportet quod voluntas, quae de potentia in actum reducitur dum aliquid vult, semper actu velit, sed solum quando est in aliqua dispositione determinata. Voluntas autem Dei, quae est actus purus, semper est in actu volendi.
And in like manner it is not necessary that the will (which is reduced from potentiality to act, when it wills something), should always be in the act of volition; but only when it is in a certain determinate disposition. But God's will, which is pure act, is always in the act of volition.