Thomas Aquinas, Summa Theologiae

Objection 1: It would seem that the soul understands all things through innate species. For Gregory says, in a homily for the Ascension (xxix in Ev.), that "man has understanding in common with the angels." But angels understand all things through innate species: wherefore in the book De Causis it is said that "every intelligence is full of forms." Therefore the soul also has innate species of things, by means of which it understands corporeal things.

Objection 2: Further, the intellectual soul is more excellent than corporeal primary matter. But primary matter was created by God under the forms to which it has potentiality. Therefore much more is the intellectual soul created by God under intelligible species. And so the soul understands corporeal things through innate species.

Objection 3: Further, no one can answer the truth except concerning what he knows. But even a person untaught and devoid of acquired knowledge, answers the truth to every question if put to him in orderly fashion, as we find related in the Meno (xv seqq.) of Plato, concerning a certain individual. Therefore we have some knowledge of things even before we acquire knowledge; which would not be the case unless we had innate species. Therefore the soul understands corporeal things through innate species.

On the contrary, The Philosopher, speaking of the intellect, says (De Anima iii, 4) that it is like "a tablet on which nothing is written."

I answer that, Since form is the principle of action, a thing must be related to the form which is the principle of an action, as it is to that action: for instance, if upward motion is from lightness, then that which only potentially moves upwards must needs be only potentially light, but that which actually moves upwards must needs be actually light. Now we observe that man sometimes is only a potential knower, both as to sense and as to intellect. And he is reduced from such potentiality to act---through the action of sensible objects on his senses, to the act of sensation---by instruction or discovery, to the act of understanding. Wherefore we must say that the cognitive soul is in potentiality both to the images which are the principles of sensing, and to those which are the principles of understanding. For this reason Aristotle (De Anima iii, 4) held that the intellect by which the soul understands has no innate species, but is at first in potentiality to all such species.

But since that which has a form actually, is sometimes unable to act according to that form on account of some hindrance, as a light thing may be hindered from moving upwards; for this reason did Plato hold that naturally man's intellect is filled with all intelligible species, but that, by being united to the body, it is hindered from the realization of its act. But this seems to be unreasonable. First, because, if the soul has a natural knowledge of all things, it seems impossible for the soul so far to forget the existence of such knowledge as not to know itself to be possessed thereof: for no man forgets what he knows naturally; that, for instance, the whole is larger than the part, and such like. And especially unreasonable does this seem if we suppose that it is natural to the soul to be united to the body, as we have established above (Question 76, Article 1): for it is unreasonable that the natural operation of a thing be totally hindered by that which belongs to it naturally. Secondly, the falseness of this opinion is clearly proved from the fact that if a sense be wanting, the knowledge of what is apprehended through that sense is wanting also: for instance, a man who is born blind can have no knowledge of colors. This would not be the case if the soul had innate images of all intelligible things. We must therefore conclude that the soul does not know corporeal things through innate species.

Reply to Objection 1: Man indeed has intelligence in common with the angels, but not in the same degree of perfection: just as the lower grades of bodies, which merely exist, according to Gregory (Homily on Ascension, xxix In Ev.), have not the same degree of perfection as the higher bodies. For the matter of the lower bodies is not totally completed by its form, but is in potentiality to forms which it has not: whereas the matter of heavenly bodies is totally completed by its form, so that it is not in potentiality to any other form, as we have said above (Question 66, Article 2). In the same way the angelic intellect is perfected by intelligible species, in accordance with its nature; whereas the human intellect is in potentiality to such species.

Reply to Objection 2: Primary matter has substantial being through its form, consequently it had need to be created under some form: else it would not be in act. But when once it exists under one form it is in potentiality to others. On the other hand, the intellect does not receive substantial being through the intelligible species; and therefore there is no comparison.

Reply to Objection 3: If questions be put in an orderly fashion they proceed from universal self-evident principles to what is particular. Now by such a process knowledge is produced in the mind of the learner. Wherefore when he answers the truth to a subsequent question, this is not because he had knowledge previously, but because he thus learns for the first time. For it matters not whether the teacher proceed from universal principles to conclusions by questioning or by asserting; for in either case the mind of the listener is assured of what follows by that which preceded.

Articulus 3

Argumentum 1

Ad tertium sic proceditur. Videtur quod anima intelligat omnia per species sibi naturaliter inditas.

Dicit enim Gregorius, in homilia ascensionis quod homo habet commune cum Angelis intelligere.

Sed Angeli intelligunt omnia per formas naturaliter inditas, unde in libro de causis dicitur quod omnis intelligentia est plena formis.

Ergo et anima habet species rerum naturaliter inditas, quibus corporalia intelligit.

Argumentum 2

Praeterea, anima intellectiva est nobilior quam materia prima corporalis. Sed materia prima est creata a deo sub formis ad quas est in potentia. Ergo multo magis anima intellectiva est creata a deo sub speciebus intelligibilibus. Et sic anima intelligit corporalia per species sibi naturaliter inditas.

Argumentum 3

Praeterea, nullus potest verum respondere nisi de eo quod scit.

Sed aliquis etiam idiota, non habens scientiam acquisitam, respondet verum de singulis, si tamen ordinate interrogetur, ut narratur in menone Platonis de quodam.

Ergo antequam aliquis acquirat scientiam, habet rerum cognitionem. Quod non esset nisi anima haberet species naturaliter inditas. Intelligit igitur anima res corporeas per species naturaliter inditas.

Sed Contra

Sed contra est quod philosophus dicit, in III de anima, de intellectu loquens, quod est sicut tabula in qua nihil est scriptum.

Corpus

Respondeo dicendum quod, cum forma sit principium actionis, oportet ut eo modo se habeat aliquid ad formam quae est actionis principium, quo se habet ad actionem illam, sicut si moveri sursum est ex levitate, oportet quod in potentia tantum sursum fertur, esse leve solum in potentia, quod autem actu sursum fertur, esse leve in actu. Videmus autem quod homo est quandoque cognoscens in potentia tantum, tam secundum sensum quam secundum intellectum.

Et de tali potentia in actum reducitur, ut sentiat quidem, per actiones sensibilium in sensum; ut intelligat autem, per disciplinam aut inventionem. Unde oportet dicere quod anima cognoscitiva sit in potentia tam ad similitudines quae sunt principia sentiendi, quam ad similitudines quae sunt principia intelligendi.

Et propter hoc Aristoteles posuit quod intellectus, quo anima intelligit, non habet aliquas species naturaliter inditas, sed est in principio in potentia ad huiusmodi species omnes. Sed quia id quod habet actu formam, interdum non potest agere secundum formam propter aliquod impedimentum, sicut leve si impediatur sursum ferri; propter hoc Plato posuit quod intellectus hominis naturaliter est plenus omnibus speciebus intelligibilibus, sed per unionem corporis impeditur ne possit in actum exire.

Sed hoc non videtur convenienter dictum. Primo quidem quia, si habet anima naturalem notitiam omnium, non videtur esse possibile quod huius naturalis notitiae tantam oblivionem capiat, quod nesciat se huiusmodi scientiam habere, nullus enim homo obliviscitur ea quae naturaliter cognoscit, sicut quod omne totum sit maius sua parte, et alia huiusmodi. Praecipue autem hoc videtur inconveniens, si ponatur esse animae naturale corpori uniri, ut supra habitum est, inconveniens enim est quod naturalis operatio alicuius rei totaliter impediatur per id quod est sibi secundum naturam. Secundo, manifeste apparet huius positionis falsitas ex hoc quod, deficiente aliquo sensu, deficit scientia eorum, quae apprehenduntur secundum illum sensum; sicut caecus natus nullam potest habere notitiam de coloribus. Quod non esset, si animae essent naturaliter inditae omnium intelligibilium rationes. Et ideo dicendum est quod anima non cognoscit corporalia per species naturaliter inditas.

Ad 1

Ad primum ergo dicendum quod homo quidem convenit cum Angelis in intelligendo, deficit tamen ab eminentia intellectus eorum, sicut et corpora inferiora, quae tantum existunt secundum Gregorium, deficiunt ab existentia superiorum corporum.

Nam materia inferiorum corporum non est completa totaliter per formam, sed est in potentia ad formas quas non habet, materia autem caelestium corporum est totaliter completa per formam, ita quod non est in potentia ad aliam formam, ut supra habitum est.

Et similiter intellectus Angeli est perfectus per species intelligibiles secundum suam naturam, intellectus autem humanus est in potentia ad huiusmodi species.

Ad 2

Ad secundum dicendum quod materia prima habet esse substantiale per formam, et ideo oportuit quod crearetur sub aliqua forma, alioquin non esset in actu. Sub una tamen forma existens, est in potentia ad alias. Intellectus autem non habet esse substantiale per speciem intelligibilem; et ideo non est simile.

Ad 3

Ad tertium dicendum quod ordinata interrogatio procedit ex principiis communibus per se notis, ad propria. Per talem autem processum scientia causatur in anima addiscentis. Unde cum verum respondet de his de quibus secundo interrogatur, hoc non est quia prius ea noverit; sed quia tunc ea de novo addiscit. Nihil enim refert utrum ille qui docet, proponendo vel interrogando procedat de principiis communibus ad conclusiones, utrobique enim animus audientis certificatur de posterioribus per priora.