1 Objection 1: It seems that the existence of God is self-evident. Now those things are said to be self-evident to us the knowledge of which is naturally implanted in us, as we can see in regard to first principles. But as Damascene says De Fide Orth. i, 1, 3), the knowledge of God is naturally implanted in all. Therefore the existence of God is self-evident.
1 Ad primum sic proceditur. Videtur quod Deum esse sit per se notum. Illa enim nobis dicuntur per se nota, quorum cognitio nobis naturaliter inest, sicut patet de primis principiis. Sed, sicut dicit Damascenus in principio libri sui, omnibus cognitio existendi Deum naturaliter est inserta. Ergo Deum esse est per se notum.
2 Objection 2: Further, those things are said to be self-evident which are known as soon as the terms are known, which the Philosopher 1 Poster. iii) says is true of the first principles of demonstration. Thus, when the nature of a whole and of a part is known, it is at once recognized that every whole is greater than its part. But as soon as the signification of the word God is understood, it is at once seen that God exists. For by this word is signified that thing than which nothing greater can be conceived. But that which exists actually and mentally is greater than that which exists only mentally. Therefore, since as soon as the word God is understood it exists mentally, it also follows that it exists actually. Therefore the proposition God exists is self-evident.
2 Praeterea, illa dicuntur esse per se nota, quae statim, cognitis terminis, cognoscuntur, quod philosophus attribuit primis demonstrationis principiis, in I Poster., scito enim quid est totum et quid pars, statim scitur quod omne totum maius est sua parte. Sed intellecto quid significet hoc nomen Deus, statim habetur quod Deus est. Significatur enim hoc nomine id quo maius significari non potest, maius autem est quod est in re et intellectu, quam quod est in intellectu tantum, unde cum, intellecto hoc nomine Deus, statim sit in intellectu, sequitur etiam quod sit in re. Ergo Deum esse est per se notum.
3 Objection 3: Further, the existence of truth is self-evident. For whoever denies the existence of truth grants that truth does not exist: and, if truth does not exist, then the proposition Truth does not exist is true: and if there is anything true, there must be truth. But God is truth itself: I am the way, the truth, and the life Jn. 14, 6) Therefore God exists is self-evident.
3 Praeterea, veritatem esse est per se notum, quia qui negat veritatem esse, concedit veritatem esse, si enim veritas non est, verum est veritatem non esse. Si autem est aliquid verum, oportet quod veritas sit. Deus autem est ipsa veritas, Ioann. XIV, ego sum via, veritas et vita. Ergo Deum esse est per se notum.
4 On the contrary, No one can mentally admit the opposite of what is self-evident; as the Philosopher Metaph. iv, lect. vi) states concerning the first principles of demonstration. But the opposite of the proposition God is can be mentally admitted: The fool said in his heart, There is no God Ps. 52, 1). Therefore, that God exists is not self-evident.
4 Sed contra, nullus potest cogitare oppositum eius quod est per se notum ut patet per philosophum, in IV Metaphys. et I Poster., circa prima demonstrationis principia. Cogitari autem potest oppositum eius quod est Deum esse, secundum illud Psalmi LII, dixit insipiens in corde suo, non est Deus. Ergo Deum esse non est per se notum.
5 I answer that, A thing can be self-evident in either of two ways: on the one hand, self-evident in itself, though not to us; on the other, self-evident in itself, and to us. A proposition is self-evident because the predicate is included in the essence of the subject, as Man is an animal, for animal is contained in the essence of man. If, therefore the essence of the predicate and subject be known to all, the proposition will be self-evident to all; as is clear with regard to the first principles of demonstration, the terms of which are common things that no one is ignorant of, such as being and non-being, whole and part, and such like.
If, however, there are some to whom the essence of the predicate and subject is unknown, the proposition will be self-evident in itself, but not to those who do not know the meaning of the predicate and subject of the proposition. Therefore, it happens, as Boethius says Hebdom., the title of which is: Whether all that is, is good), that there are some mental concepts self-evident only to the learned, as that incorporeal substances are not in space. Therefore I say that this proposition, God exists, of itself is self-evident, for the predicate is the same as the subject, because God is His own existence as will be hereafter shown Question 3, Article 4).
Now because we do not know the essence of God, the proposition is not self-evident to us; but needs to be demonstrated by things that are more known to us, though less known in their nature, namely, by effects.
5 Respondeo dicendum quod contingit aliquid esse per se notum dupliciter, uno modo, secundum se et non quoad nos; alio modo, secundum se et quoad nos. Ex hoc enim aliqua propositio est per se nota, quod praedicatum includitur in ratione subiecti, ut homo est animal, nam animal est de ratione hominis. Si igitur notum sit omnibus de praedicato et de subiecto quid sit, propositio illa erit omnibus per se nota, sicut patet in primis demonstrationum principiis, quorum termini sunt quaedam communia quae nullus ignorat, ut ens et non ens, totum et pars, et similia. Si autem apud aliquos notum non sit de praedicato et subiecto quid sit, propositio quidem quantum in se est, erit per se nota, non tamen apud illos qui praedicatum et subiectum propositionis ignorant. Et ideo contingit, ut dicit Boetius in libro de hebdomadibus, quod quaedam sunt communes animi conceptiones et per se notae, apud sapientes tantum, ut incorporalia in loco non esse. Dico ergo quod haec propositio, Deus est, quantum in se est, per se nota est, quia praedicatum est idem cum subiecto; Deus enim est suum esse, ut infra patebit. Sed quia nos non scimus de Deo quid est, non est nobis per se nota, sed indiget demonstrari per ea quae sunt magis nota quoad nos, et minus nota quoad naturam, scilicet per effectus.
6 Reply to Objection 1: To know that God exists in a general and confused way is implanted in us by nature, inasmuch as God is man's beatitude. For man naturally desires happiness, and what is naturally desired by man must be naturally known to him. This, however, is not to know absolutely that God exists; just as to know that someone is approaching is not the same as to know that Peter is approaching, even though it is Peter who is approaching; for many there are who imagine that man's perfect good which is happiness, consists in riches, and others in pleasures, and others in something else.
6 Ad primum ergo dicendum quod cognoscere Deum esse in aliquo communi, sub quadam confusione, est nobis naturaliter insertum, inquantum scilicet Deus est hominis beatitudo, homo enim naturaliter desiderat beatitudinem, et quod naturaliter desideratur ab homine, naturaliter cognoscitur ab eodem. Sed hoc non est simpliciter cognoscere Deum esse; sicut cognoscere venientem, non est cognoscere Petrum, quamvis sit Petrus veniens, multi enim perfectum hominis bonum, quod est beatitudo, existimant divitias; quidam vero voluptates; quidam autem aliquid aliud.
7 Reply to Objection 2: Perhaps not everyone who hears this word God understands it to signify something than which nothing greater can be thought, seeing that some have believed God to be a body. Yet, granted that everyone understands that by this word God is signified something than which nothing greater can be thought, nevertheless, it does not therefore follow that he understands that what the word signifies exists actually, but only that it exists mentally. Nor can it be argued that it actually exists, unless it be admitted that there actually exists something than which nothing greater can be thought; and this precisely is not admitted by those who hold that God does not exist.
7 Ad secundum dicendum quod forte ille qui audit hoc nomen Deus, non intelligit significari aliquid quo maius cogitari non possit, cum quidam crediderint Deum esse corpus. Dato etiam quod quilibet intelligat hoc nomine Deus significari hoc quod dicitur, scilicet illud quo maius cogitari non potest; non tamen propter hoc sequitur quod intelligat id quod significatur per nomen, esse in rerum natura; sed in apprehensione intellectus tantum. Nec potest argui quod sit in re, nisi daretur quod sit in re aliquid quo maius cogitari non potest, quod non est datum a ponentibus Deum non esse.
8 Reply to Objection 3: The existence of truth in general is self-evident but the existence of a Primal Truth is not self-evident to us.
8 Ad tertium dicendum quod veritatem esse in communi, est per se notum, sed primam veritatem esse, hoc non est per se notum quoad nos.