1 Objection 1: It would seem that the intellect is not a passive power. For everything is passive by its matter, and acts by its form. But the intellectual power results from the immateriality of the intelligent substance. Therefore it seems that the intellect is not a passive power.
1 Ad secundum sic proceditur. Videtur quod intellectus non sit potentia passiva. Patitur enim unumquodque secundum materiam; sed agit ratione formae. Sed virtus intellectiva consequitur immaterialitatem substantiae intelligentis. Ergo videtur quod intellectus non sit potentia passiva.
2 Objection 2: Further, the intellectual power is incorruptible, as we have said above Question 79, Article 6). But if the intellect is passive, it is corruptible De Anima iii, 5). Therefore the intellectual power is not passive.
2 Praeterea, potentia intellectiva est incorruptibilis, ut supra dictum est. Sed intellectus si est passivus, est corruptibilis, ut dicitur in III de anima. Ergo potentia intellectiva non est passiva.
3 Objection 3: Further, the agent is nobler than the patient, as Augustine Gen. ad lit. xii, 16) and Aristotle De Anima iii, 5) says. But all the powers of the vegetative part are active; yet they are the lowest among the powers of the soul. Much more, therefore, all the intellectual powers, which are the highest, are active.
3 Praeterea, agens est nobilius patiente, ut dicit Augustinus XII super Gen. ad Litt., et Aristoteles in III de anima. Potentiae autem vegetativae partis omnes sunt activae, quae tamen sunt infimae inter potentias animae. Ergo multo magis potentiae intellectivae, quae sunt supremae, omnes sunt activae.
4 On the contrary, The Philosopher says De Anima iii, 4) that to understand is in a way to be passive.
4 Sed contra est quod philosophus dicit, in III de anima, quod intelligere est pati quoddam.
5 I answer that, To be passive may be taken in three ways. Firstly, in its most strict sense, when from a thing is taken something which belongs to it by virtue either of its nature, or of its proper inclination: as when water loses coolness by heating, and as when a man becomes ill or sad. Secondly, less strictly, a thing is said to be passive, when something, whether suitable or unsuitable, is taken away from it. And in this way not only he who is ill is said to be passive, but also he who is healed; not only he that is sad, but also he that is joyful; or whatever way he be altered or moved.
Thirdly, in a wide sense a thing is said to be passive, from the very fact that what is in potentiality to something receives that to which it was in potentiality, without being deprived of anything. And accordingly, whatever passes from potentiality to act, may be said to be passive, even when it is perfected. And thus with us to understand is to be passive. This is clear from the following reason. For the intellect, as we have seen above Question 78, Article 1), has an operation extending to universal being.
We may therefore see whether the intellect be in act or potentiality by observing first of all the nature of the relation of the intellect to universal being. For we find an intellect whose relation to universal being is that of the act of all being: and such is the Divine intellect, which is the Essence of God, in which originally and virtually, all being pre-exists as in its first cause. And therefore the Divine intellect is not in potentiality, but is pure act.
But no created intellect can be an act in relation to the whole universal being; otherwise it would needs be an infinite being. Wherefore every created intellect is not the act of all things intelligible, by reason of its very existence; but is compared to these intelligible things as a potentiality to act. Now, potentiality has a double relation to act. There is a potentiality which is always perfected by its act: as the matter of the heavenly bodies Question 58, Article 1).
And there is another potentiality which is not always in act, but proceeds from potentiality to act; as we observe in things that are corrupted and generated. Wherefore the angelic intellect is always in act as regards those things which it can understand, by reason of its proximity to the first intellect, which is pure act, as we have said above. But the human intellect, which is the lowest in the order of intelligence and most remote from the perfection of the Divine intellect, is in potentiality with regard to things intelligible, and is at first like a clean tablet on which nothing is written, as the Philosopher says De Anima iii, 4).
This is made clear from the fact, that at first we are only in potentiality to understand, and afterwards we are made to understand actually. And so it is evident that with us to understand is in a way to be passive; taking passion in the third sense. And consequently the intellect is a passive power.
5 Respondeo dicendum quod pati tripliciter dicitur. Uno modo, propriissime, scilicet quando aliquid removetur ab eo quod convenit sibi secundum naturam, aut secundum propriam inclinationem; sicut cum aqua frigiditatem amittit per calefactionem, et cum homo aegrotat aut tristatur. Secundo modo, minus proprie dicitur aliquis pati ex eo quod aliquid ab ipso abiicitur, sive sit ei conveniens, sive non conveniens. Et secundum hoc dicitur pati non solum qui aegrotat, sed etiam qui sanatur; non solum qui tristatur, sed etiam qui laetatur; vel quocumque modo aliquis alteretur vel moveatur.
Tertio modo, dicitur aliquid pati communiter, ex hoc solo quod id quod est in potentia ad aliquid, recipit illud ad quod erat in potentia, absque hoc quod aliquid abiiciatur. Secundum quem modum, omne quod exit de potentia in actum, potest dici pati, etiam cum perficitur. Et sic intelligere nostrum est pati. Quod quidem hac ratione apparet. Intellectus enim, sicut supra dictum est, habet operationem circa ens in universali. Considerari ergo potest utrum intellectus sit in actu vel potentia, ex hoc quod consideratur quomodo intellectus se habeat ad ens universale.
Invenitur enim aliquis intellectus qui ad ens universale se habet sicut actus totius entis, et talis est intellectus divinus, qui est Dei essentia, in qua originaliter et virtualiter totum ens praeexistit sicut in prima causa. Et ideo intellectus divinus non est in potentia, sed est actus purus. Nullus autem intellectus creatus potest se habere ut actus respectu totius entis universalis, quia sic oporteret quod esset ens infinitum. Unde omnis intellectus creatus, per hoc ipsum quod est, non est actus omnium intelligibilium, sed comparatur ad ipsa intelligibilia sicut potentia ad actum.
Potentia autem dupliciter se habet ad actum. Est enim quaedam potentia quae semper est perfecta per actum; sicut diximus de materia corporum caelestium. Quaedam autem potentia est, quae non semper est in actu, sed de potentia procedit in actum; sicut invenitur in generabilibus et corruptibilibus. Intellectus igitur angelicus semper est in actu suorum intelligibilium, propter propinquitatem ad primum intellectum, qui est actus purus, ut supra dictum est. Intellectus autem humanus, qui est infimus in ordine intellectuum, et maxime remotus a perfectione divini intellectus, est in potentia respectu intelligibilium, et in principio est sicut tabula rasa in qua nihil est scriptum, ut philosophus dicit in III de anima.
Quod manifeste apparet ex hoc, quod in principio sumus intelligentes solum in potentia, postmodum autem efficimur intelligentes in actu. Sic igitur patet quod intelligere nostrum est quoddam pati, secundum tertium modum passionis. Et per consequens intellectus est potentia passiva.
6 Reply to Objection 1: This objection is verified of passion in the first and second senses, which belong to primary matter. But in the third sense passion is in anything which is reduced from potentiality to act.
6 Ad primum ergo dicendum quod obiectio illa procedit de primo et secundo modo passionis, qui sunt proprii materiae primae. Tertius autem modus passionis est cuiuscumque in potentia existentis quod in actum reducitur.
7 Reply to Objection 2: Passive intellect is the name given by some to the sensitive appetite, in which are the passions of the soul; which appetite is also called rational by participation, because it obeys the reason Ethic. i, 13). Others give the name of passive intellect to the cogitative power, which is called the particular reason. And in each case passive may be taken in the two first senses; forasmuch as this so-called intellect is the act of a corporeal organ. But the intellect which is in potentiality to things intelligible, and which for this reason Aristotle calls the possible intellect De Anima iii, 4) is not passive except in the third sense: for it is not an act of a corporeal organ. Hence it is incorruptible.
7 Ad secundum dicendum quod intellectus passivus secundum quosdam dicitur appetitus sensitivus, in quo sunt animae passiones; qui etiam in I Ethic. dicitur rationalis per participationem, quia obedit rationi. Secundum alios autem intellectus passivus dicitur virtus cogitativa, quae nominatur ratio particularis. Et utroque modo passivum accipi potest secundum primos duos modos passionis, inquantum talis intellectus sic dictus, est actus alicuius organi corporalis. Sed intellectus qui est in potentia ad intelligibilia, quem Aristoteles ob hoc nominat intellectum possibilem, non est passivus nisi tertio modo, quia non est actus organi corporalis. Et ideo est incorruptibilis.
8 Reply to Objection 3: The agent is nobler than the patient, if the action and the passion are referred to the same thing: but not always, if they refer to different things. Now the intellect is a passive power in regard to the whole universal being: while the vegetative power is active in regard to some particular thing, namely, the body as united to the soul. Wherefore nothing prevents such a passive force being nobler than such an active one.
8 Ad tertium dicendum quod agens est nobilius patiente, si ad idem actio et passio referantur, non autem semper, si ad diversa. Intellectus autem est vis passiva respectu totius entis universalis. Vegetativum autem est activum respectu cuiusdam entis particularis, scilicet corporis coniuncti. Unde nihil prohibet huiusmodi passivum esse nobilius tali activo.