It may be strange to some that there are philosophical objections raised by Christians against arguments for belief in God. For example, St. Anselm’s “Ontological Proof” (as it would come to be called) was taken under a critical lens when Thomas Aquinas (1225-1274) took consideration of the argument in his epic Summa Theologiae (ST hereafter). Over the last year or so, I have written numerous defenses of Anselm’s argument as well as criticisms so as to see if we have a legitimate and defensible argument for God’s existence.
Gaunilo and Kant’s criticism aside, there are several other considerable objections to the argument that I think are serious enough to address. Two in particular come to mind. Mortimer J. Adler (1980) makes the point in his book How to Think About God that existential propositions do not entail logical necessity. As he writes at length:
No existential proposition can be self-evidently true or necessarily true. When we have direct perceptual acquaintance with a particular individual, the existence of that individual is evident to us, but the proposition which asserts that the individual exists is not self-evident, nor is its truth necessary. Self-evident propositions are propositions which we know to be true directly from our understanding of their component terms, not by process of reasoning or inference. (Adler 1980: 104)
An existential proposition is a claim that asserts something regarding the existence of a thing. So, for example, “God exists” is an existential proposition because we are making a claim about the subject (God) – namely, that it exists. When we affirm the existence of things we do so in three ways:
- We can assert that it does in fact exist;
- We can assert that it exists contingently;
- We can assert that it exists necessarily.
However, when we do make any of these three claims, the truth of the proposition that asserts existence is itself not a necessary truth. The strange thing about this whole discussion is that philosophers or Christians who find Anselm’s proof logically valid will agree to what has been said above regarding existential propositions, except for one problem: the uniqueness of the proposition “God exists” is such that it is an existential proposition unlike all the others; particularly, that it is also self-evidently and necessarily true.
Even if this view was correct, then what is the need for a logical demonstration? It doesn’t seem that there is much sense to establish the truth of a self-evidently true proposition via logical deduction. As Adler argues, “What is self-evident does not need to be established by reasoning” (106).
The second considerable objection comes from Thomas Aquinas, who in his ST makes the counter-claim that although God’s existence may be self-evident to Himself, it is not to us. St. Anselm in his Proslogion made the argument for the existence of God from the very concept of God. Otherwise stated, if we can know what God is then we can know that God is (i.e., from God’s essence we can conclude God’s existence). Aquinas however, disagreed. He believed that since we have no direct or immediate access to the divine essence, we can’t deduce from this alone that God exists. Hence, according to Aquinas, God’s existence is not self-evident and we thus need a demonstrative proof in its place.
Diogenes Allen (1985) has an interesting way of showing this. Aquinas’ argument that God’s existence is not self-evident is sort of like lacking a middle term in Aristotelian logic. For instance, consider this argument:
- All x‘s are y’s.
- P is an x.
- Therefore, p is a y.
In this example, x is the middle term. In relation to our discussion, if we knew what causes existence to belong to God then we would have the middle term. In the proposition “God exists” we do not know what connects the predicate (exists) to its subject (God). The obvious reason for this is that God’s essence is unknowable to us. Therefore, it is a legitimate pursuit for Aquinas to try and make a proof establishing God’s existence.
One author makes the criticism of Aquinas’ position that “[t]his critique centered upon [his] charge that not everyone shared the same concept of God and consequently the argument will only convince those with a similar notion. He further claimed that even if one could share the same concept of God, one would have no idea what this sequence of words really means.” The author here is referring to Article 1, Question 2: Whether the existence of God is self-evident. In Reply to Objection 2, Aquinas writes:
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. (here)
If this is the passage that the author is referring to, and I have understood him correctly, then his criticism of Aquinas – that one ought to have a full understanding of the concept for the argument to be successful – is mistaken. For instance, Aquinas made the distinction between two kinds of propositions: (i) absolutely self-evident and (ii) contextually self-evident.
For example, the proposition that “man is an animal” is absolutely self-evident because “the predicate is included in the essence of the subject” (1a, q2). Hence, “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.”
However, “God exists” is contextually self-evident because the nature of God cannot be grasped by the human intellect. Though the proposition may be self-evident in itself, it will not be to those who do not have an understanding of all the relevant concepts (Smith, 156). Through his rejection Anselm’s proof, Aquinas finds that there are instead legitimate reasons in causal arguments (i.e., from effects in the world) for the existence of God. It is for these reasons that I believe Aquinas’ objection still stands.
Adler, Mortimer. How to Think About God. 1980. Lexington, KY.
Allen, Diogenes. Philosophy for Understanding Theology. 1985. Atlanta, GA: John Knox Press.
Smith, George. Why Atheism? 2001. Promotheus Books.