Does Aquinas deny that we can ever know God?
In Part I of the Summa Theologiae, Aquinas postulates answers to questions of whether we can know God’s essence through (Question 12) and if such knowledge can be accurately conveyed through human language, specifically for ‘naming’ God (Question 13). Question 12 and 13 follow Aquinas’ Five Ways (Quinque viæ), in which he establishes that God is the ‘uncaused causer’ of all things (primum movens immobile) and exits as “pure actuality” without potential (actus purus et perfectus); this is significant to Questions 12 and 13, because it is on the basis of these established attributes of God, that Aquinas questions to what extent the human intellect is able to know, and articulate this knowledge, of a being who is totally unlike themselves. Although Aquinas makes clear in Questions 12 that man’s capacity for knowledge of God is limited by our differences to God; most significantly our corporeal and finite existence compared to God’s infinite and non-corporeal essence, I would argue that he does not seek to deny all possibility of man knowing God. To deny such a possibility would be contra to his understanding of man’s purpose, as outlined in his first two treatises of the Summa Theologiae and his conception of Natural Law, which he articulates in Question 94 of the Prima Secundæ Partis. Question 13, which Aquinas dedicates to answering the question of whether we can accurately convey knowledge of God through language, reflects Aquinas’ ideas about the limited human intellect from Question 12; Aquinas’ belief that we can obtain knowledge of what God is, is reflected in his support for positive language used to ‘name’ God, and his belief that our capacity to understand God “as He is in Himself” (1.13.12) is limited, is consistent with his argument against the use of univocal language to speak of God’s essence. Aquinas’ preference analogical language, conveyed in Question 13: “This name ‘God’…is then neither univocally nor equivocally, but analogically” (1.13.10), supports my thesis that Aquinas does not what to deny all possible knowledge of God and rather, the Summa is an attempt to establish a means of affirming positive knowledge about God, whilst also maintaining that any knowledge about God in the “created intellect” will be imperfect in its conception of God as “pure actuality” (1.12.7).
In Question 12 in Part 1 of the Summa, I would argue that Aquinas views the rational nature of human beings and the nature of God’s essence as actus purus, as previously affirmed in his Five Ways, as necessary conditions for our ability to “see the essence of God” (1.12.1). Question 12 has its basis in Aquinas’ view of human telos, as articulated in his Treatise on the Last End and Treatise on Law which were inspired by Aristotle’s discussion of ‘Eudaimonia’ in Nicomachean Ethics and Augustine’s De Vera Religion and seek to demonstrate that man’s purpose, and his final happiness, are found in seeing God: “So then no one can know the eternal law, as it is in itself, except the blessed who see God in His Essence. But every rational creature knows it in its reflection, greater or less. For every knowledge of truth is a kind of reflection and participation of the eternal law, which is the unchangeable truth” (2.93.2). The view that man’s rationality is one of the two necessary conditions of our being able to know God, is present in Article 1 of Question 12: “For the ultimate perfection of the rational creature is to be found in that which is the principle of its being; since a thing is perfect so far as it attains to its principle” (1.12.1), which shows that Aquinas saw man’s telos as being intrinsically linked to use of his rationality. Such a belief leads to his argument that since a purpose must be achievable by man, it must be possible for man’s intellect (our rational capacity) to “see” God, which he affirms in Question 12: “if we suppose that the created intellect could never see God, it would either never attain to beatitude, or its beatitude would consist in something else beside God; which is opposed to faith” (1.12.1). From this argument, it appears to me that Aquinas is affirming, rather than denying, on the basis of reason, that we must be able to know God in some sense, because it is our purpose to do so. I would argue that Aquinas also sees God’s being actus purus as the second reason why: “it must be absolutely granted that the blessed see the essence of God” (1.12.1). In Article 7 of Question 12, Aquinas claims that: “Everything is knowable according to its actuality" and from this assertion, it necessarily follows that God, who is actus purus, must therefore be knowable in his entirety; as Aquinas states: “everything is knowable according as it is actual, God, who is pure act without any admixture of potentially, is himself supremely knowable” (1.12.1). From these arguments, the first based on human rationality and the second on God’s essence as actus purus, it can be argued that Aquinas believed that God can be known in this life by the human intellect. However, I would argue that such a reading is not entirely justified on the basis that in the Prima Secundæ Partis Aquinas states that the perfect happiness which comes with contemplating the goodness of Divine Essence can only be attained in the life to come: “And thus it will have its perfection through union with God as with that object, in which alone man's happiness consists” (2.3.8), and therefore it is not possible for man to obtain their telos in this mortal life alone. This view that knowledge of God’s goodness is not fully obtainable in this physical life is also present in Article 11 of Question 12: “God cannot be seen in His essence by a mere human being except he be separated from this mortal life”. Such a belief is supported by Aquinas on the basis of scripture: “Man shall not see Me, and live” (Ex. 32:20), as well as on the grounds that the distance between us the finite and material “knowers” and God the infinite and transcend “known”, is too great for us to claim to have knowledge of our subject; as Aquinas states: “knowledge is regulated according as the thing known is in the knower. But the thing known is in the knower according to the mode of the knower. Hence the knowledge of every knower is ruled according to its own nature" (1.12.4). On this basis, Aquinas argues that: “It is impossible for any created intellect to comprehend God" (1.12.7) whilst the soul, through which the rational intellect operates, is limited by the constraints of the material body. Aquinas’ dualist presentation of the ‘body-soul’ relationship in A Q: is similar to my understanding of the Aristotle’s perception of: “the soul which is called mind” which he believes “cannot reasonably be regarded as blended with the body” (De Anima III,4; 429a10–b9) and like Aristotle, who did believed that the mind was limited by the body, Aquinas affirms that it is: “beyond the power of the intellect of our soul in the state of its present life, united as it is to the body [to know God’s essence]”. From Aquinas’ presentation of the intellect as limited within the temporal body, it can be argued that he did not believe that we could ever fully know God in our current form. Aquinas’ christian faith makes me inclined to believe that he would have read 1 Corinthians 15:43-44: “It is sown a natural body, it is raised a spiritual body. There is a natural body, and there is a spiritual body”, as a literal affirmation of our potential to become one in God’s body upon deaths, and thus able to reduce the gap between our existence and God’s as actus purus, to the extent that we could gain complete post-mortem knowledge of him. This reading of Aquinas suggests that he did believe it possible for the intellect to “see the essence of God” when “God, by His grace, unites Himself to the created intellect, as an object made illegible to it” (1.12.4).
In Article 12 of Question 12, Aquinas uses his concept of God as primum movens immobile, as shown through his Five Ways, to establish that knowledge of God can be gained from observation of his creation; as Aquinas states: “because they are His effects and depended on their cause, we can be led from them so far as to know of God ‘whether he exists’ [as established in the Five Ways], and to know of Him what must necessarily belong to him, as the first cause of all things, exceeding all things caused by him. Hence we can know that His relationship with creatures so far as he be the cause of them all” (1.12.12). In this argument Aquinas uses Natural Theology and does not rely on Divine Revelation to establish what can be known about God; this suggests that Davies is correct in his assertion that in his writing in the Summa: “There is a distinction in Aquinas about “what can be affirmed of God by reason” and “what can be asserted of God on the basis of revelation”. This form of knowledge which Aquinas bases on “natural reason”, he argues can give us an understanding of what God is not, on the basis that they are caused and therefore contingent, whereas God is primum movens immobile and therefore necessary; as Aquinas states: “creatures differ from Him, inasmuch as He is not in any way part of what is caused by Him” (1.12.12). This distinction between God and all things which are note God, provides justification Aquinas’ claim that it is justified to speak about God in the negative: “Negative names applied to God…express the distance of the creature from Him, or His relation to something else, or rather, the relation of creatures to Himself”(1.13.2); on this basis it could be argued that we do possess knowledge of God and can accurately express this knowledge through means of the Via Negativa, as formulated by Maimonides’ in his Guide to The Perplexed. However, for Aquinas, knowledge derived from observation of God’s “creatures” only “signifies” the “perfections” of God, “such as goodness, life and the like”; from this, it can be argued that full knowledge of God’s essence is not obtained through the contingent, temporal and changeable world, due to its being radially different from the necessary, infinite and constant essence of God. Aquinas’ further conveys the limitations of Natural Theology to provide us will complete knowledge of God, through his critique of Chrysostom’s reading of John 1:18, in which he argues that there is a distinction between “the vision of comprehension” and being able to “see the essence of God”. This difference is significant because, although we can “see the essence of God” using our “created intellect”, as established in Question 12, Article 1, we cannot “comprehend” the essence of God, because man cannot comprehend infinity from within his finite world; as Aquinas states: “it is clearly impossible for ay created intellect to know God in an infinite degree. Hence it is impossible that it should comprehend God”. Aquinas argues that the distinction between our ability to “comprehend” God and “see the essence of God” is a valid one, on the basis that man can ‘see’ a triangle, but it does not necessarily follow that he would “comprehend” it; as Aquinas states: “if anyone knows by scientific demonstration that a triangle has three angles equal to two right angles, he comprehends that truth; whereas if anyone accepts it as a probable opinion because wise men or most men teach it”. Although Aquinas uses this distinction between ‘knowing’ and ‘comprehending’ to demonstrate that we can know God without comprehending his infinite essence, I am not convinced by this argument, nor by his defence of his position in Question 12, Article 1: “God is not said to be not existing as if He did not exist at all, but because He exists above all that exists; inasmuch as He is His own existence. Hence it does not follow that He cannot be known at all, but that He exceeds every kind of knowledge; which means that He is not comprehended”, which I do not believe sufficiently proves that knowledge, defined as: “Facts, information, and skills acquired through experience or education; the theoretical or practical understanding of a subject”, can be considered distinct from ‘comprehension’. On this basis, it could be argued that Aquinas considered himself to have shown that knowledge of an infinite God who “exceeds every kind of knowledge” is possible, however, I would argue that without comprehension it is doubtful that we could use ‘knowledge’ about God univocally with ‘knowledge’ about mathematics or about God’s “creatures”. The latter is the position which I believe Aquinas held to be true, on the basis that he refuted the use of univocal language to speak of God: “Thus also this term "wise" applied to man in some degree circumscribes and comprehends the thing signified; whereas this is not the case when it is applied to God; but it leaves the thing signified as incomprehended, and as exceeding the signification of the name. Hence it is evident that this term "wise" is not applied in the same way to God and to man. The same rule applies to other terms. Hence no name is predicated univocally of God and of creatures” (1.13.5). This position suggests that although Aquinas saw God as knowable to man, he did not equate knowledge of the Divine with knowledge of the material world; thus although he did not deny that we could ever have knowledge of God, Aquinas’ Summa Theologiae suggests that our knowledge of God is radically different from all the other forms of knowledge which we possess. This point is compounded by Article 11 in Question 13, in which God is ‘named’ as: “He Who Is”, which emphasises the complete ‘otherness’ of our knowledge about God and reaffirms Aquinas’ belief of God as primum movens immobile, by showing that nothing other than God can ‘cause’ anything in God, and thus only a name from God can be given to God.
In Article 6 of Question 12, Aquinas states that it is “the light of glory” which enables us to “see God the more perfectly”; such a claim suggests that it is possible for us to know God through religious faith and contrarily, I would argue, to have no knowledge of God if we have no “desire” to bring “divine light” (1.12.11) into our intellectual darkness. Aquinas’ argument presents a hierarchical model of the ability of man to know God, with those who have a greater desire to know God, gaining greater “clarity” in their view of him: “he will have a fuller participation of the light of glory who has more charity, because where there is greater charity, there is more desire; and desire in a certain degree makes the one desiring apt and prepared to receive the object desired” (1.12.6). From this argument, I believe that it is possible to deduce that the people who lack the Theological Virtue of “charity” (caritas) and a desire to develop such a virtue, will have a very limited vision of God’s essence, perhaps to the extent where it is justified to say that they have no knowledge of God. This position can be supported on the grounds that in Article 5 of Question 12, Aquinas argues that this “divine grace” is necessary for elevating natural reason to the point where the intellect is able can “see the essence of God”: “since the natural power of the created intellect does not avail to enable it to see the essence of God…it is necessary that the power of understanding should be added by divine grace". From this, I would argue that Aquinas does allow for arguments which deny some individuals the ability to know God’s essence on the basis that they lack “divine grace” which can only be obtained through Divine Revelation, such as that which Aquinas cites in Apocalypse 21:23 (1.12.5).
The ability to convey knowledge about God’s essence through language is central to Aquinas’ Question 13, for the reason that he believes that our ability to ‘name’ God is a measure of our ability to know him: “a thing is named by us according as we understand it” (1.13.2) and as Aquinas states: “‘words are the signs of what we understand,’ it must needs be that in naming things we follow the process of intellectual knowledge” (2.7.1). In Question 13, Aquinas demonstrates that “Univocal terms mean absolutely the same thing” (1.13.10) are inadequate for talking about God because God is radically unlike anything which man’s intellect can comprehend, similarly “equivocal terms” which have “absolutely different [meanings]” are equally as problematic when applied to God, because God does have a “relationship with creatures so far as to be the cause of them all” (1.12.12). For these reasons, a third way of language is required and this for Aquinas was analogical language, which he demonstrated to be proportional analogies and attributional analogies through an Aristotle-inspired paradigm: “either according as many things are proportionate to one, thus for example "healthy" predicated of medicine and urine in relation and in proportion to health of a body, of which the former is the sign and the latter the cause: or according as one thing is proportionate to another, thus "healthy" is said of medicine and animal, since medicine is the cause of health in the animal body” (1.13.5). This means of speaking about God, I would argue, illustrates Aquinas intention to affirm that do have some knowledge of God and therefore that we can speak about him in positive terms, however, that we must do so in a way which acknowledges that we will never be able to fully know or express God’s simplicity as primum movens immobile and actus purus et perfectus, as Aquinas states: “And as God is simple, and subsisting, we attribute to Him abstract names to signify His simplicity, and concrete names to signify His substance and perfection, although both these kinds of names fail to express His mode of being, forasmuch as our intellect does not know Him in this life as He is” (1.13.1).
I would argue that the greatest limitation in our ability to perfectly know God, according to Aquinas, is our finite corporeal nature, which makes us irreconcilably different to God who, for Aquinas, is primum movens immobile and actus purus et perfectus. These bodily limitations do not prohibit us from knowing God in terms of his causes through utilisation of our natural reason, nor does it totally prohibit us from speaking about God through analogical language, which conveys both the distinction of God’s essence from ourselves, as well as the creational relationship which he has to us as his creation. However, I would argue, that Aquinas only believes that we can only know God fully and perfectly in the post-mortem Beatific Vision (visio beatifica), like that in Psalm 36 which Aquinas refers to in Article 4 of Question 12, in which we have the opportunity to be united with God unencumbered by our corporeal or finite existence. This is also the view which, I would argue, Aquinas is referring to in his Treatise on the Last End, when he refers to the possibly that man will be free of all desires, and thus will be able to enjoy perfect happiness: “perfect happiness the intellect needs to reach the very Essence of the First Cause. And thus it will have its perfection through union with God as with that object, in which alone man's happiness consists” (2.3.8). Such claims, I acknowledge, are cannot be established as ‘truthful’ on the basis of Ayer’s Verification Principle, however, these are the beliefs which I would argue Aquinas was conveying through his Summa.