Thomas Aquinas, Summa Theologiae

Objection 1: It would seem that an angel does not know himself. For Dionysius says that "the angels do not know their own powers" (Coel. Hier. vi). But, when the substance is known, the power is known. Therefore an angel does not know his own essence.

Objection 2: Further, an angel is a single substance, otherwise he would not act, since acts belong to single subsistences. But nothing single is intelligible. Therefore, since the angel possesses only knowledge which is intellectual, no angel can know himself.

Objection 3: Further, the intellect is moved by the intelligible object: because, as stated in De Anima iii, 4 understanding is a kind of passion. But nothing is moved by or is passive to itself; as appears in corporeal things. Therefore the angel cannot understand himself.

On the contrary, Augustine says (Gen. ad lit. ii) that "the angel knew himself when he was established, that is, enlightened by truth."

I answer that, As is evident from what has been previously said (Question 14, Article 2; Question 54, Article 2), the object is on a different footing in an immanent, and in a transient, action. In a transient action the object or matter into which the action passes is something separate from the agent, as the thing heated is from what gave it heat, and the building from the builder; whereas in an immanent action, for the action to proceed, the object must be united with the agent; just as the sensible object must be in contact with sense, in order that sense may actually perceive. And the object which is united to a faculty bears the same relation to actions of this kind as does the form which is the principle of action in other agents: for, as heat is the formal principle of heating in the fire, so is the species of the thing seen the formal principle of sight to the eye.

It must, however, be borne in mind that this image of the object exists sometimes only potentially in the knowing faculty; and then there is only knowledge in potentiality; and in order that there may be actual knowledge, it is required that the faculty of knowledge be actuated by the species. But if it always actually possesses the species, it can thereby have actual knowledge without any preceding change or reception. From this it is evident that it is not of the nature of knower, as knowing, to be moved by the object, but as knowing in potentiality. Now, for the form to be the principle of the action, it makes no difference whether it be inherent in something else, or self-subsisting; because heat would give forth heat none the less if it were self-subsisting, than it does by inhering in something else. So therefore, if in the order of intelligible beings there be any subsisting intelligible form, it will understand itself. And since an angel is immaterial, he is a subsisting form; and, consequently, he is actually intelligible. Hence it follows that he understands himself by his form, which is his substance.

Reply to Objection 1: That is the text of the old translation, which is amended in the new one, and runs thus: "furthermore they," that is to say the angels, "knew their own powers": instead of which the old translation read---"and furthermore they do not know their own powers." Although even the letter of the old translation might be kept in this respect, that the angels do not know their own power perfectly; according as it proceeds from the order of the Divine Wisdom, Which to the angels is incomprehensible.

Reply to Objection 2: We have no knowledge of single corporeal things, not because of their particularity, but on account of the matter, which is their principle of individuation. Accordingly, if there be any single things subsisting without matter, as the angels are, there is nothing to prevent them from being actually intelligible.

Reply to Objection 3: It belongs to the intellect, in so far as if is in potentiality, to be moved and to be passive. Hence this does not happen in the angelic intellect, especially as regards the fact that he understands himself. Besides the action of the intellect is not of the same nature as the action found in corporeal things, which passes into some other matter.

Articulus 1

Argumentum 1

Ad primum sic proceditur. Videtur quod Angelus seipsum non cognoscat.

Dicit enim dionysius, VI cap. Angel. Hier., quod Angeli ignorant proprias virtutes. Cognita autem substantia, cognoscitur virtus.

Ergo Angelus non cognoscit suam essentiam.

Argumentum 2

Praeterea, Angelus est quaedam substantia singularis, alioquin non ageret, cum actus sint singularium subsistentium. Sed nullum singulare est intelligibile. Ergo non potest intelligi. Et ita, cum Angelo non adsit nisi intellectiva cognitio, non poterit aliquis Angelus cognoscere seipsum.

Argumentum 3

Praeterea, intellectus movetur ab intelligibili, quia intelligere est quoddam pati, ut dicitur in III de anima.

Sed nihil movetur aut patitur a seipso; ut in rebus corporalibus apparet.

Ergo Angelus non potest intelligere seipsum.

Sed Contra

Sed contra est quod Augustinus dicit, II super Gen. Ad litt., quod Angelus in ipsa sua conformatione, hoc est illustratione veritatis, cognovit seipsum.

Corpus

Respondeo dicendum quod, sicut ex supra dictis patet, obiectum aliter se habet in actione quae manet in agente, et in actione quae transit in aliquid exterius. Nam in actione quae transit in aliquid exterius, obiectum sive materia in quam transit actus, est separata ab agente, sicut calefactum a calefaciente, et aedificatum ab aedificante. Sed in actione quae manet in agente, oportet ad hoc quod procedat actio, quod obiectum uniatur agenti, sicut oportet quod sensibile uniatur sensui, ad hoc quod sentiat actu. Et ita se habet obiectum unitum potentiae ad huiusmodi actionem, sicut forma quae est principium actionis in aliis agentibus, sicut enim calor est principium formale calefactionis in igne, ita species rei visae est principium formale visionis in oculo.

Sed considerandum est quod huiusmodi species obiecti quandoque est in potentia tantum in cognoscitiva virtute, et tunc est cognoscens in potentia tantum; et ad hoc quod actu cognoscat, requiritur quod potentia cognoscitiva reducatur in actum speciei.

Si autem semper eam actu habeat, nihilominus per eam cognoscere potest absque aliqua mutatione vel receptione praecedenti. Ex quo patet quod moveri ab obiecto non est de ratione cognoscentis inquantum est cognoscens, sed inquantum est potentia cognoscens.

Nihil autem differt, ad hoc quod forma sit principium actionis, quod ipsa forma sit alii inhaerens, et quod sit per se subsistens, non enim minus calor calefaceret si esset per se subsistens, quam calefacit inhaerens. Sic igitur et si aliquid in genere intelligibilium se habeat ut forma intelligibilis subsistens, intelliget seipsum. Angelus autem, cum sit immaterialis, est quaedam forma subsistens, et per hoc intelligibilis actu. Unde sequitur quod per suam formam, quae est sua substantia, seipsum intelligat.

Ad 1

Ad primum ergo dicendum quod littera illa est antiquae translationis, quae corrigitur per novam, in qua dicitur, praeterea et ipsos, scilicet Angelos, cognovisse proprias virtutes; loco cuius habebatur in alia translatione, et adhuc et eos ignorare proprias virtutes.

Quamvis etiam littera antiquae translationis salvari possit quantum ad hoc, quod Angeli non perfecte cognoscunt suam virtutem, secundum quod procedit ab ordine divinae sapientiae, quae est Angelis incomprehensibilis.

Ad 2

Ad secundum dicendum quod singularium quae sunt in rebus corporalibus, non est intellectus, apud nos, non ratione singularitatis, sed ratione materiae, quae est in eis individuationis principium. Unde si aliqua singularia sunt sine materia subsistentia, sicut sunt Angeli, illa nihil prohibet intelligibilia esse actu.

Ad 3

Ad tertium dicendum quod moveri et pati convenit intellectui secundum quod est in potentia. Unde non habet locum in intellectu angelico; maxime quantum ad hoc quod intelligit seipsum.

Actio etiam intellectus non est eiusdem rationis cum actione quae in corporalibus invenitur, in aliam materiam transeunte.