The Coherence of Theism
2
Introduction
What does it mean to say that something is incoherent? The answer is appealingly simple. In philosophy, a state of affairs is incoherent if its description contains a contradiction. Two paradigmatic examples of incoherence commonly found in philosophical discussions are the “square circle” and “married bachelor.” That these are simply contradictory pairings of words that do not and cannot pick out things in the real world is something we can know by means of rational reflection alone without needing to undertake an investigation or conduct an experiment. It follows that any mathematician who did seek a Euclidian proof or disproof of the “square circle” (or any sociologist who applied for a research grant to prove or disprove the existence of the “married bachelor”) would be acting irrationally. To express all this somewhat differently: If it can be shown that something contains or entails a contradiction, we have the strongest possible grounds for affirming that it does not exist. We would not then need any evidence to falsify the claim that it exists and, a fortiori, would never be justified in looking at evidence purporting to prove its existence.
The question we are asking is whether the concept of God is a logically coherent one. For if it can be shown that it is not logically coherent even ask if God exists (if it can be shown that the claim "God exists" is analogous to the claim "Square circles exist"—absurd and disprovable by rational reflection alone) then the whole debate over the evidence for and against the existence of God is irrational and unnecessary. Before coming to the evidence, it is therefore necessary to defend the concept of God against the charge of incoherence.
The first issue, given satisfactory criteria for what qualifies as a person, will be whether it is coherent to suppose that an immaterial person exists; the second, whether the attributes of God (such as omnipotence, omniscience, omnipresence, and so on) entail logical contradictions; and the third, whether these same attributes are coherent in view of certain features of human experience—such as the fact that God is said to be perfectly good and all-powerful while our world is filled with evil and suffering. [1]
Definition of Key Terms
Before going further, it will be helpful to define some key terms. I will understand “God” to mean An immaterial person that is omnipotent, omniscient, omnipresent, necessary, eternal and perfectly good. And I will understand “incoherent" to mean that some state of affairs is logically impossible because its description contains a contradiction. Note, however, that philosophers recognise two different kinds of logical incoherence that will be of use in this discussion: Strict logical incoherence and broad logical incoherence. I will briefly define these now.
In a case of strict logical incoherence, the contradiction is explicit in the description of something. The phrases square circle and married bachelor are both good examples of this. The words square and circle together mean, “a round polygon that has four equal sides,” and married and bachelor together mean, “an unmarried man who is married.” All that is required to see the incoherence in each case is an understanding of the words in the description. A polygon cannot be round and have four sides and a man cannot be married and unmarried. Both commit us to saying, "P is Q and not-Q" which is a contradiction. Contradictory properties cannot coexist because they are mutually exclusive. If an object is black all over then, ipso facto, it is not white all over—and visa versa. A thing with contradictory properties cannot be exemplified: It cannot possibly exist.
In a case of broad logical incoherence, on the other hand, the contradiction is entailed by the description of something. The sentence, The Prime Minister of England is a prime number is an example of this. Here the contradiction is only implicit in the description because “Prime Minister” and “prime number" are not in direct logical opposition in the way that “square circle” and “married bachelor” are. To see the incoherence, we need to follow out the entailments of the sentence. In the present case, we would do this as follows. A prime number, being a mathematical abstractum, is immaterial; a Prime Minister, being the head of an elected government of human beings, is material. The sentence, The Prime Minister is a prime number therefore commits us to saying that something is both immaterial and material which is, finally, a strict logical contradiction akin to “square circle” or “married bachelor.” We are saying, incoherently, that, “P is Q and not-Q.”
With this understanding of God and of the two subtypes of incoherence in hand, we will now consider whether the concept of An immaterial person who is omnipotent, omniscient, omnipresent, necessary, eternal and perfectly good is logically incoherent in either the strict or the broad sense. I will begin in the next section with the fundamental question of whether or not an immaterial person of any kind is logically coherent, before discussing the logical coherence of an immaterial person with the attributes ascribed to God in classical theology. On this subject, Oxford professor of philosophy, Richard Swinburne, has written an entire book called The Coherence of Theism. In the following pages, I will be paraphrasing his arguments.
Footnotes
[1] Referring to "features of human experience" in a discussion of this nature involves a slight relaxation of the distinction between analytic and synthetic propositions. In doing so I take a hint from Wittgenstein who stressed the importance of including very basic empirical propositions of the sort we are taught as children (such as that, "the Earth is round and men's heads are not full of sawdust and cars do not grow out of the ground") among our first principles. "Propositions of the form of empirical propositions," he writes, "and not only propositions of logic, form the foundation of all operating with thoughts."
[1] Referring to "features of human experience" in a discussion of this nature involves a slight relaxation of the distinction between analytic and synthetic propositions. In doing so I take a hint from Wittgenstein who stressed the importance of including very basic empirical propositions of the sort we are taught as children (such as that, "the Earth is round and men's heads are not full of sawdust and cars do not grow out of the ground") among our first principles. "Propositions of the form of empirical propositions," he writes, "and not only propositions of logic, form the foundation of all operating with thoughts."