“no one who understands what God is can conceive that God does not exist” (Anselm 1077)
Chapter links:
St Anselm’s ontological argument
Whether God is within our understanding
Gaunilo’s ‘lost island’ response to Anselm
Descartes’ Ontological argument
Kant’s 2nd objection: existence is not a predicate
Malcolm’s ontological argument
Kant’s 1st objection: necessity doesn’t imply existence
Can we rationally believe God’s possibility?
Introduction
In 1077 AD St Anselm created an argument for the existence of God which came to be known (thanks to Kant) as the Ontological argument. Ontology refers to what exists.
Ontological arguments are a priori, based solely on an analysis of the concept of God. They essentially argue that if you think carefully about what God is, you’ll understand that God must exist.
The argument has proven controversial, with many of its critics actually being religious themselves. It’s less popular as a defence of theistic belief amongst religious philosophers than the cosmological and teleological arguments. Those arguments identify features of the world (motion, causation, complexity/purpose) and attempt, a posteriori, to infer God’s existence as the explanation for the existence of the universe, or for why the universe is the way it is.
The a priori ontological argument is trying to do something quite different. It’s actually difficult to put one’s finger on what the argument is doing. First impressions of the argument vary widely, but a common one, shared by its first major critic Gaunilo, is to think the argument is absurd; either a joke, or foolishness. Nonetheless what’s fascinating about the argument is that even if one has that reaction, it’s difficult at first glance to figure out a real criticism of it. The argument has provoked serious attention from many great philosophers, whether positive or negative. There could be more to the argument than first impressions might suggest. Russell captured this well:
“it is easier to feel convinced that [the Ontological Argument] must be fallacious than it is to find out precisely where the fallacy lies.” (Bertrand Russell 1945)
St Anselm’s ontological argument (ꜛ)
In Proslogion 2, Anselm argues that there is a distinction between existing in the mind, and existing in reality, illustrated by the way a painter has an idea in their mind before painting it in reality
He then points to Psalm 14:1 “the fool says in his heart, ‘there is no God’”. This shows that atheists must have an idea of the God they are rejecting in their mind. Anselm identifies this as a point of agreement between atheists and theists. Both can agree on the definition of God. His argument then claims to deduce that God exists just from God’s definition:
P1. God is defined as the greatest conceivable being.
P2. It is greater to exist in reality than the mind alone.
P3. God exists in the mind.
C1. Therefore, God exists in reality.
The force of Anselm’s argument is that God cannot be an idea that exists in the mind alone (as an Atheist thinks). That would be incoherent, since then we could conceive of something greater, i.e., God also existing in reality. Yet, God is the greatest being, so conceiving of anything greater is incoherent. So, our idea of God must therefore be of a being that exists in reality. To say that God does not exist in reality is effectively to say that the greatest being is not the greatest being. It is self-contradictory.
“that, than which nothing greater can be conceived, cannot exist in the understanding alone: then it can be conceived to exist in reality; which is greater. Therefore, if that, than which nothing greater can be conceived, exists in the understanding alone, the very being, than which nothing greater can be conceived, is one, than which a greater can be conceived. But obviously this is impossible. Hence, there is no doubt that there exists a being, than which nothing greater can be conceived, and it exists both in the understanding and reality.” (Anselm 1077)
Malcolm and Hartshorne were responsible for renewing interest in the Ontological argument in the 20th century. They think Anselm made the strongest version of the argument in Proslogion chapter 3 which revolves around the distinction between necessity and contingency:
- A necessary being is one which must exist, because it does not depend on anything else for its existence.
- A contingent being is one which could either exist or not, because it depends on something else to exist.
Anselm argues:
P1. A necessary being whose nonexistence is impossible is greater than a contingent being whose nonexistence is possible.
C1. Therefore, God (as the greatest conceivable being), necessarily exists.
Malcolm interprets Anselm’s term ‘greater’ as referring to degrees of limitation, such as dependence on other things for existence. God must be unlimited, without any of the contingencies of ordinary beings which make their non-existence possible. So, a being greater than which none may be conceived is one whose nonexistence is impossible. Hartshorne calls this insight “Anselm’s discovery”. In his later replies to critics, Anselm captures the key move of the ontological argument: If an impossibly non-existent being is logically possible, then it must exist.
“if [a being greater than which cannot be conceived] can be thought of, then certainly it necessarily exists” (Anselm 1079)
Whether God is within our understanding (ꜛ)
Gaunilo objects to Anselm’s third premise, the notion that God is in our mind/understanding. He brings up a traditional argument from classical theology, that God is beyond our understanding. We might be able to conceive of a human we’ve never experienced, because of our general knowledge of what humans are like. But in the case of God, we have nothing to go off, because of God’s uniqueness in his transcendent unknowability. Gaunilo grants that Anselm’s description of God gives us something to think about, and prompt an attempt to conceive of what they describe. But he doubts that this attempt gives us a genuine understanding of the divine nature. Gaunilo regards this as preventing Anselm from proceeding in his proof
“Of God, or a being greater than all others, I could not conceive at all”
(Gaunilo 1079)
“So much for the assertion that this supreme nature already is in my understanding.” (Gaunilo 1079)
Anselm responds that he didn’t mean God is in the mind in the sense of us having full knowledge of God’s substantive nature. He uses the term ‘in intellectu’, which means ‘can be conceived or thought about’, not ‘fully understood’. He draws an analogy:
if you say that, because it is not completely understood, it cannot be understood at all and cannot be in the mind, then you must say [equally] that one who cannot see the purest light of the sun directly does not see daylight, which is the same thing as the light of the sun. Surely then ‘that-than-which-a-greater-cannot-be-thought’ is understood and is in the mind (Anselm 1079)
Just because we cannot look directly at the sun, doesn’t mean we can’t see by sunlight.
Similarly, just because we can’t understand what God is, doesn’t mean we can’t understand that whatever God is, God is the greatest conceivable being.
Evaluation defending the ontological argument:
We can develop Anselm’s response to show that Gaunilo misunderstood premise 3, and demanded more understanding than Anselm’s argument actually requires. Some concepts involve a hierarchy which must have a highest point. Not all do so, e.g., numbers form a hierarchy, but there is no such thing as the biggest number. Plantinga calls the highest point of a hierarchical concept its ‘intrinsic maximum’. He illustrates that knowledge has an intrinsic maximum, because knowing every truth would be unsurpassable. There cannot coherently be any higher level of knowledge than that.
We can apply this to Anselm’s term ‘greatness’, which has the intrinsic maximum in a being with all the omni-qualities. Such a being would be unsurpassable in greatness, because there is no degree of any perfection which they lack. Plantinga builds this point into his definition of God, as a ‘maximally great’ being.
We can understand the idea of a being at the top of the greatness hierarchy, even if such a being is actually beyond our understanding in its nature. We don’t need to understand the nature of a maximally great being, in order to follow the ontological argument’s reasoning about it. That, if it’s greater to exist, then a maximally great being must exist. Or that if necessary existence is greater than contingent, then a maximally great being necessarily exists. So, Anselm’s defence works because Gaunilo overlooks the distinction between knowing God to be the greatest being, and knowing what it is to be the greatest being. His argument only needs the former, not the latter.
Gaunilo’s ‘lost island’ response to Anselm (ꜛ)
Gaunilo attempts a ‘reductio ad absurdum’ critique, which aims to show that taking an argument to its fullest logical implications produces an absurd result. This began a tradition of critique sometimes called ‘parodies’ of the ontological argument. Gaunilo argued that if we apply Anselm’s reasoning to another case, like an island, we can an absurd result:
I can conceive of the greatest possible island.
According to Anselm’s reasoning, it is greater to exist in reality and the mind, than in the mind alone.
The greatest possible island is in my mind.
So, it follows that the greatest possible island must exist.
This critique would work for the greatest possible version of everything. It’s sometimes called the ‘overload’ objection, because it shows Anselm’s reasoning implies reality would be overloaded with greatest possible things.
“I should not admit that this being is in my understanding and concept even in the way in which many objects whose real existence is uncertain and doubtful, are in my understanding and concept. For it should be proved first that this being itself really exists somewhere; and then, from the fact that it is greater than all, we shall not hesitate to infer that it also subsists in itself …
It is said that somewhere in the ocean is an island … it is more excellent than all other countries … Now if some one should tell me that there is such an island, I should easily understand his words … But suppose that he went on to say, as if by a logical inference: “You can no longer doubt that this island which is more excellent than all lands exists somewhere, since you have no doubt that it is in your understanding. And since it is more excellent not to be in the understanding alone, but to exist both in the understanding and in reality, for this reason it must exist. For if it does not exist, any land which really exists will be more excellent than it; and so the island already understood by you to be more excellent will not be more excellent.”
If a man should try to prove to me by such reasoning that this island truly exists, and that its existence should no longer be doubted, either I should believe that he was jesting, or I know not which I ought to regard as the greater fool: myself, supposing that I should allow this proof; or him, if he should suppose that he had established with any certainty the existence of this island.” (Gaunilo 1079)
Anselm responded that it’s not a valid test of the ontological argument to apply its reasoning to anything other than God. He argues God is a unique case, because it is a being whose non-existence is inconceivable.
Descartes develops this sort of response, arguing that God’s essence include necessary existence, while contingent things like islands do not. An island by definition is land enclosed by water. So its existence depends on other things which themselves might not exist, e.g., water, a planet, a sun, etc. Therefore, no matter how great or perfect a contingent thing might be, it’s still contingent, and so could not exist.
Evaluation defending the ontological argument:
This reply defeats Gaunilo because it shows that a priori reasoning can only prove the existence of a necessary being. A priori reasoning involves things like the analysis of the definition of concepts.
Essentially: when we analyse a contingent being a priori, we find that it is a contingent thing which can either exist or not. We therefore cannot know a priori whether it does actually exist. But when we analyse a necessary being a priori, we find that its non-existence is impossible, so we can know that it does actually exist.
When we analyse contingent being a priori, we can discover their existence conditions, but not whether those conditions are fulfilled. E.g., we can know a priori that the greatest island depends on water to exist, but we cannot know a priori whether that water exists, nor therefore the island itself. The existence conditions of contingent beings are found in their definition, but whether those conditions are fulfilled is not.
These being the reasons we cannot determine the existence of a contingent being a priori, the opposite is the case with a necessary being. A priori analysis of a necessary being tells us that it contains its reason for existence within itself. Its existence conditions do not involve or depend on anything external to themselves. Therefore, there is nothing regarding the fulfilment of its existence conditions which is not already captured in its definition. So, we can know a priori that a necessary being must exist. This explains why a priori demonstration works only in the case of a necessary being, not a contingent being like an Island.
Descartes’ Ontological argument (ꜛ)
“the idea of God, or a supremely perfect being, is one which I find within me just as surely as the idea of any shape or number. And my understanding that it belongs to his nature that he always exists is no less clear and distinct than is the case when I prove of any shape or number that some property belongs to its nature” (Descartes 1641)
Descartes significantly shifts the epistemological grounding and philosophical method of the ontological argument. His rationalist epistemology holds that we can gain substantive knowledge about reality purely a priori. Anselm’s ontological argument is also a priori, but operates by proving a contradiction in God’s non-existence through formal argument. Descartes rejects this method, instead claiming the ontological argument functions through direct apprehension of God’s existence through intellectual intuition.
Anselm is often called the father of scholasticism, a medieval intellectual tradition that used systematic reasoning to examine and defend theological beliefs. They drew on Aristotle’s logic, giving an important role to analysing propositions and constructing deductive arguments. Propositions were often analysed as a subject (what the proposition is about) and a predicate (what is asserted of it). Anselm’s ontological argument reflects this scholastic emphasis on logical demonstration, proceeding through a deductive proof to argue that denying God’s existence leads to a contradiction. His conclusion that “God exists”, can be understood as ‘God’ being the subject, and ‘exists’ being the predicate.
Descartes criticised scholasticism as more useful for explaining truths already known than for discovering new truths. For Descartes, discovering new foundational knowledge requires intuition, which involves direct intellectual apprehension. Intuitions are immediate and self-evident. Grasping them does not require careful reasoning from premises to a conclusion.
We can bring ideas before our mind and apprehend truths about them due to the clarity and distinctness with which they are perceived. He calls this the ‘natural light’ of reason, and treats such perception as a source of certainty. His famous ‘cogito ergo sum’ is an example of intuition. We can immediately grasp our existence, without needing to carefully follow logical argument to reach the conclusion that we exist. Descartes illustrates intuition with it being impossible to bring a triangle before our mind whose angles do not equal 180 degrees.
He applies intuition to the idea of a supremely perfect being:
- A supremely perfect being contains all perfections.
- Necessary existence is a perfection, because it means God depends on nothing else for existence, and is an eternal being.
- So, we can clearly and distinctly perceive that necessary existence belongs to the supremely perfect nature.
Descartes also compares the inseparability of God and existence to that of a mountain and a valley. He acknowledges that this connection does not establish that any mountains or triangles exist. The distinctive feature of God is that necessary existence itself belongs to God’s nature. So, the intellectual means by which we know God’s existence has the same method and certainty as mathematical truths.
Descartes did put his argument into a deductive form, probably meant as a temporary tool to help appreciate how God can be known through intuition. He says ‘formal argument’ is not required, but seems to think it can nonetheless help with the reflection needed to gain the right intuition:
P1: The idea of a supremely perfect being is one which contains all perfections.
P2: Existence is a perfection
C3: God exists
Kant’s 2nd objection: existence is not a real predicate (ꜛ)
A predicate is a describing word. A ‘real’ predicate is a word that describes an attribute or characteristic of a thing.
The ontological argument seems to assume that existence is a predicate. Descartes implies that perfection is a defining attribute of God. Anselm argues God must exist in order to be God. They both try to show that denying God’s existence denies what God is. This seems to treat ‘existence’ as if it described a defining property a thing possesses. That would make the word ‘exists’ a predicate.
Kant objects that this misunderstands what existence is. If existence were a predicate, it would be added to our concept of a thing that exists. Our concept of a thing that exists would then be conceptually different to our idea of that same thing when not existing.
If I say my cat is black, I describe the cat, because the word ‘black’ is a predicate which describes the subject ‘cat’. But if I say my cat exists, I do not describe a feature of the cat. I may be describing reality in a general sense, so Kant allows that existence can be a ‘logical predicate’. However, existence is not a ‘real predicate’, meaning it does not describe an attribute of a thing itself.
Kant illustrates with 100 thalers (coins). He asks us to compare 100 coins existing in reality, with 100 coins as only a mental concept in our mind. Of course there is a type of difference. The coins in reality can be touched, used, thrown around, etc. But what Kant wants to emphasise is that there is no conceptual difference between coins in reality, vs coins in the mind. This proves that existence is not a predicate. If existence were a predicate, it would describe a characteristic of the real coins which the mental coins do not have. But 100 coins is just 100 coins, whether they exist or not. They are described by the predicates of 100, round, shiny, metal, etc.
So it seems that Kant has distinguished what a thing is from whether it exists. This is a problem for the ontological argument, which claims we can know whether God exists, from thinking about what God is.
Anselm thinks it’s greater to exist, but that assumes that existence has some bearing on what a thing is, which assumes existence is a predicate. Descartes claims existence is a perfection which a supremely perfect being would have, but that also assumes existence is a predicate.
However, Kant’s objection might fail to target Descartes’ version of the ontological argument. Descartes adopts a different epistemological method to Anselm. For Descartes, the foundation of knowledge is provided through rational intuition, when the intellect grasps certain truths with immediacy, as opposed to a careful process of deductive reasoning which follows premises to a conclusion. Descartes thinks deductive reasoning has a place, but thinks intuition is the foundation for knowledge. What matters for our purposes here is that Descartes thinks the proof of God provided by the ontological argument can work through intuition. He illustrates intuition by pointing out that we cannot conceive of a triangle without internal degrees which add up to 180 degrees. In the same way, we cannot bring the idea of God before our mind separated from existence. So Descartes doesn’t think the ontological argument needs to work through a chain of reasoning which attributes predicates to subjects at all. Therefore he cannot be accused here of mistakenly treating existence as a predicate.
Evaluation defending the ontological argument:
Furthermore, Malcolm shows that Kant fails to undermine Anselm’s style of argumentation. Malcolm identifies two versions of Anselm’s argument, in chapters 2 and 3 of the proslogion respectively. He thinks Kant undermined the version in chapter 2, which seems to assume existence is a predicate because it is relevant to the greatness (or lack thereof) of a being. However in chapter 3, Anselm brings in the concept of necessary existence, which Malcolm thinks can be defended as a predicate.
Coins are contingent things which can exist or not. This explains why they have the same conceptual description in either case. If (insert description of coins here) can exist, or (insert description of coins here) can not exist, then, existence is clearly irrelevant to how we describe or characterise the coins. So existence is not a predicate.
The issue is, existence in a general sense might not be a predicate, but that doesn’t prove that the more specific case of necessary existence is not a real predicate. The ontological argument is concerned with a very specific type of existence. Kant might be right about the existence of cats and coins, without having proven that he’s right about God.
When we describe a being as greatest, supremely perfect or unlimited, we are describing a characteristic of it. We are describing that it has no dependencies and therefore cannot fail to exist. It has none of the dependent limitations of ordinary beings which can mean that they can fail to exist. So Necessary existence is therefore a real predicate. It characterizes a being a containing its reason for existence within itself and as impossibly non-existent.
Unlike with coins, we cannot hold God’s nature constant while comparing his existence to his non-existence. So ultimately, Kant makes the same mistake as Gaunilo. They both take a conclusion they drew from contingent beings, like islands or coins, and misapply that to an argument about a necessary being.
Malcolm’s ontological argument (ꜛ)
Norman Malcolm’s version of the ontological argument explicitly employs modal logic, which studies reasoning about what is possible (could be true), necessary (must be true) or impossible (cannot be true). Modal arguments use the logical relationships between these categories to deduce conclusions from their premises. Malcolm uses this approach to argue that, if God’s existence is possible but cannot be contingent, it must be necessary.
Malcolm interprets Anselm’s proslogion chapters 2 and 3 as presenting two distinct versions of the ontological argument. The first to do with God’s existence being greater than non-existence. The second to do with God’s necessity. Malcolm thinks Kant defeated Anselm’s argument in proslogion 2. Since, claiming that existing in reality makes a being greater than existing only in the mind, assumes that existence adds to a thing’s concept. However, he defends Anselm’s second argument. He regards necessary existence as a perfection, since it describes that a thing is impossibly non-existent. So Necessary existence is a predicate, and does add something to a thing’s concept.
Malcolm thinks the term ‘unlimited’ best clarifies what Anselm was getting at by describing God as the greatest conceivable being. He takes unlimited to imply that God cannot contingently exist, since then God could cease existing, which would imply an incoherent dependence on external conditions. Nor can God contingently not exist, since then something could create God, which would also incoherently imply that God is limited in depending on that thing. Malcolm uses this to deduce that God necessarily exists:
P1. God is by definition an unlimited being
P2. If God exists, then God cannot cease existing, so God would exist necessarily.
P3. If God does not exist, nothing can create God, so God would be impossible
P4. God is not impossible.
C1. Therefore, God exists necessarily.
Since Leibniz, proponents of the ontological argument have accepted that it depends on God being a logically coherent concept. Malcolm does not provide a general proof of God’s coherence, but argues that there is no special reason to presume incoherence. He concludes that the burden of proof is on the critics of the argument to prove God impossible. Specific allegations of incoherence should be answered individually, rather than requiring a general proof of coherence before the argument can proceed. In any case, Malcolm’s aim is to vindicate Anselm’s original insight, that if the concept of God is coherent at all, then God must exist.
Malcolm points to this quote from Anselm’s reply to Gaunilo:
“If it [the thing a greater than which cannot be conceived] can be conceived at all it must exist. For no one who denies or doubts the existence of a being a greater than which is inconceivable, denies or doubts that if it did exist its non-existence, either in reality or in the understanding, would be impossible. For otherwise it would not be a being a greater than which cannot be conceived. But as to whatever can be conceived but does not exist: if it were to exist its non-existence either in reality or in the understanding would be possible. Therefore, if a being a greater than which cannot be conceived, can even be conceived, it must exist.” (Anselm 1079, quoted in Malcolm 1960).
Malcolm remarks of this passage:
“What Anselm has proved is that the notion of contingent existence or of contingent nonexistence cannot have any application to God. His existence must either be logically necessary or logically impossible. The only intelligible way of rejecting Anselm’s claim that God’s existence is necessary is to maintain that the concept of God, as a being a greater than which cannot be conceived, is self-contradictory or nonsensical” (Malcolm 1960).
Malcolm’s interpretation of Anselm is that neither contingent existence nor contingent non-existence can apply to God. Therefore, the only way to deny God’s existence is to think God is necessarily non-existent, i.e., impossible, due to being incoherent.
Kant’s 1st objection: necessity doesn’t imply existence (ꜛ)
Kant’s 1st objection (in the order they appear in his book, the critique of pure reason) is quite different from his second, more famous objection, which claimed that existence is not a predicate. In his first objection, he argues that even if necessary existence were a predicate of God, that would not prove that God actually existed.
To those who thinks his 2nd objection failed, this might appear more promising. It does not focus on contingent things like coins, which Malcom argued got Kant’s 2nd objection into trouble. It develops an insight which goes back to Gaunilo. Gaunilo rejected inference from understanding a description of a supremely great being to establishing that such a being exists in reality. Gaunilo also opened himself up for critique by using a contingent thing (the perfect island) to develop this point. But the underlying insight may be more promising. In Kant’s development, it states that the ontological argument conflates necessity in mental judgement with necessity in reality.
“The unconditioned necessity of judgments … is not an absolute necessity of things.” (Kant 1781).
This critique also seems to better answer Descartes’ ‘intuition’ grounding for the ontological argument. Grasping necessary existence as inseparable from God’s nature does not establish that anything possesses that nature.
Also more promising is that Kant applies this critique to an example of necessity in judgement, using Descartes’ illustration of a triangle.
Kant argues:
A triangle necessarily has three sides.
This means that if a triangle exists, then it necessarily has three sides.
A judgement of necessity thereby tells us how something must exist, if it exists.
Similarly, mentally grasping God as necessarily existing (Descartes), or as predicated with necessary existence (Anselm & Malcolm), only shows that if God exists, then God exists necessarily.
So Kant is distinguishing a necessary connection between concepts from the necessary existence of something answering to those concepts. The ontological argument might prove that existence is essential to God, but this only tells us somehow about how God would exists, if God existed.
“the illusion of this logical necessity has proved so powerful that when one has made a concept a priori of a thing that was set up so that its existence was comprehended within the range of its meaning, one believed one could infer with certainty that because existence necessarily pertains to the object of this concept, i.e., under the condition that I posit this thing as given (existing), its existence can also be posited necessarily” (Kant 1781).
However, Malcolm accuses Kant’s 1st critique of incoherence. Since, it accepts God’s necessary existence as an a priori truth, yet also tries to allow that God’s non-existence is possible. This seems to accept the concept of God as a coherent idea, but deny that God must exist. Malcolm objects that if God is a being defined by necessary existence, then God is a being which cannot possibly fail to exist. The only way to reject God’s existence, on Malcolm’s account, is to say that the concept of God actually is incoherent. One cannot accept the concept of God as logically possible, but then think God could either exist or not, since for Malcolm, only contingent things could exist or not.
“I think that Caterus, Kant, and numerous other philosophers have been mistaken in supposing that the proposition ‘God is a necessary being’ (or “God necessarily exists”) is equivalent to the conditional proposition ‘If God exists then He necessarily exists’ … Can anything be clearer than that the conjunction ‘God necessarily exists but it is possible that He does not exist’ is self-contradictory?” (Malcolm 1960).
Malcolm’s reasoning for this is that a maximally great or unlimited being cannot have any of the dependencies of ordinary contingent beings. It therefore cannot contingently exist, since then it would depend on something which would be a limitation. Nor can it contingently not exist, since then it could be created by something on which it would then depend, which would be a limitation.
Malcolm thinks this proves that God either necessarily doesn’t exist (is impossible) or necessarily exists. This defends Anselm’s original claim, that if the definition of God is coherent and possible, then God must exist.
Evaluation criticising the ontological argument:
Malcolm’s defence can be defeated by distinguishing between types of necessity. The issue arises when he moves from God’s non-contingency, to God being either necessary or impossible. By which he means logically necessary and logically impossible. A being is logically necessary if it is contradictory to deny that it exists. A being is logically impossible if it is incoherent. So Malcolm clearly needs this to be the type of necessity & impossibility involved in the argument. Since when he argues God is not impossible, he means God is not incoherent. And when he concludes God necessarily exists, he means that it is contradictory to deny God’s existence.
Malcolm thinks that if a being is conceivably non-existent, then “it would depend on other things both for coming into and continuing in existence”. This claims that logical contingency entails contingency in being. This is where Hick objects.
Propositions can be either logically contingent, logically necessary, or logically impossible. There is no other option.
Malcolm thinks the proposition ‘God exists’ is necessarily true. So if we deny it, we have to defend its contingency or impossibility. Malcolm then seems to think the only way a proposition about a being’s existence could be contingent, is if that being itself is contingent. But by definition, an unlimited being can’t be contingent. So if ‘God exists’ is logically possible, Malcolm thinks the only remaining option is that ‘God exists’ is necessarily true.
However, there is another option Malcolm has not adequately excluded. “God exists” can be logically contingent without requiring that God is a contingent being. Hick introduces another type of necessity. And shows that Malcolm’s description of God as non-dependent only establishes this other type of necessity, not logical necessity.
A non-contingent being could be ontologically necessary, meaning non-dependent, eternal, and self-existent (aseity). There’s no contradiction in supposing such a being to not exist:
- If it exists, it cannot cease existing, making it ontologically necessary.
- If it does not exist, it cannot come into existence, making it ontologically impossible.
Proving God non-contingent only proves that God is defined as a very special being (eternal, non-dependent, etc). If such a being existed, its existence would be ontologically necessary. But there’s no reason why we should presume such a being must exist. No contradiction arises in the conception of such a being as non-existent.
A priori analysis can therefore specify how such a being would exist if it did, but not whether it actually does exist.
The proposition ‘God exists’ is contingent. Neither its truth nor its falsity follows from the concept alone; in principle it could be true or false. Ascribing contingency to the proposition ‘God exists’ is not ascribing contingency to God’s being, in the sense of dependence or the capacity to begin or cease existing. We aren’t saying God ‘happens’ to exist, or not exist. As if it were down to chance, or some other kind of dependency. We are saying that reality either has such a being, or it doesn’t. There either has always been, and always will be, such a being. Or, there never was and never will be. Either alternative is logically possible. So, God’s existence cannot be known a priori. It’s a metaphysical question about the kind of reality we are in. Hick concludes that whether God exists is a ‘sheer fact’.
So, Malcolm’s description of God as a non-contingent being at most establishes ontological necessity or impossibility. He is left without justification for his move to God’s necessity through denying God’s impossibility. Hick’s distinction between types of necessity defends Gaunilo and Kant’s insight that necessity in mental judgement doesn’t entail actual existence.
Evaluation defending the ontological argument:
Malcolm’s point is successful because it blocks what Hartshorne called ‘empirical’ attacks on the ontological argument. These attempt to accept the logical possibility of God yet deny the logical necessity of god’s existence. If God’s existence is not necessary, it must be contingent.
However, it is very difficult to understand contingency when applied to God. God is an eternal being and thus causeless. Contingency is understood as some sort of causal dependency on something else.
“Such a causeless yet contingent existence is without connection with our ordinary ways of understanding contingency … They [Hume, Kant & Hick] accuse Anselm of violating rules; but they violate the elementary rule that logically contingent matters are intelligible in genetic and causal terms, or not at all.” (Hartshorne 1977)
Supposing that God’s non-existence could be logically contingent is absurd given what God is. So, we are left with Malcolm and Hartshorne’s position, that God is either logically impossible or logically necessary.
Can we rationally believe that God is possible? (ꜛ)
Hume argues that no being’s existence can be demonstrated a priori, because no being’s non-existence is an inconceivable contradiction. He consequently rejects the notion of necessary existence as lacking a consistent meaning.
“there is an evident absurdity in pretending to demonstrate a matter of fact, or to prove it by any arguments a priori” (Hume 1779)
Hume reaches this conclusion through his empiricism and his ‘fork’, which distinguishes types of truths and the types of reasoning capable of knowing them:
A priori reasoning analyses the relations between ideas to discover necessary truths. These are true by definition, intuition or demonstration, and therefore cannot be denied without contradiction. E.g. “2+2=4″ and “a batchelor is an unmarried man”.
A posteriori reasoning investigates matters of fact to discover contingent truths. These are true because of the way the world is, and therefore can be denied without contradiction. E.g. ‘The sun will rise tomorrow’.
The concept of a necessary being mixes factual and logical truth together. It implies that purely logical a priori reasoning can determine a matter of fact in the singular case of God’s existence. Hume rejects the idea of a necessary being as failing to mark an exception to this split. On Hume’s empiricism, we gain our ideas from experience. Imagination allows us to then apply modal concepts like possibility and necessity to those ideas.
“It will still be possible for us, at any time, to conceive the non-existence of what we formerly conceived to exist; nor can the mind ever lie under a necessity of supposing any object to remain always in being; in the same manner as we lie under a necessity of always conceiving twice two to be four.” (Hume 1779)
Hume’s argument is:
- A priori reasoning establishes necessary truths which cannot be denied without contradiction.
- If something is conceivable, it cannot involve a contradiction.
- Whatever we conceive of as existing, we can also conceive as not existing.
- Therefore, no being’s non-existence involves a contradiction, and so no being’s existence can be proven a priori:
“The words, therefore, necessary existence, have no meaning; or, which is the same thing, none that is consistent.” (Hume 1779)
Through acts of imagination we can add ideas of beings into our conception of reality and subtract them. The idea of a necessary being is one we are unable to remove from our imagined concept of reality. But anything we can imagine into our conception of reality, can also simply not be imagined into it. So, our mind is incapable of forming the idea of, or giving meaning to, the idea of a being which we cannot conceive to not exist. In other words, no being’s non-existence is an inconceivable contradiction. So, we cannot intelligibly believe any being’s existence to be logically necessary.
However, Hume might be granting too much power to the imagination to determine what’s logically possible. He thinks our ability to imagine God’s non-existence, shows that God’s non-existence is possible. This assumes that conceivability entails possibility. Plantinga’s distinction of necessity from self-evidence challenges this. A proposition can be necessarily true without our faculties, like imagination, recognising its necessity. So apparent conceivability need not establish genuine possibility. Our mind might simply be failing to recognise an impossibility. So there’s still room for a necessary being.
Plantinga offers a modest defence of the premise that God is possible as rational to accept, to prove that theism is rational. He concedes that a rational person could reject it, or simply suspend judgement. Nevertheless, he argues that he doesn’t have to conclusively demonstrate God’s coherence to be rational in believing God’s coherence. Opposing sides of a philosophical dispute can remain rationally defensible despite disagreement. Plantinga therefore appeals to the role of considered judgement. We examine a proposition, assess objections, and consider its connections with our other beliefs.
There are various critiques of God’s nature and the consistency of theistic belief.
- The paradox of the stone
- The Euthyphro dilemma
- The incompatibility of free will and omniscience
- The logical problem of evil
If the judgement that God is possible remains compelling after critical examination of such issues, that is a basis to reasonably accept it.
“But since it is rational to accept their central premiss, they do show that it is rational to accept that conclusion.” (Plantinga 1974)
Evaluation criticising the ontological argument
However, Plantinga has not adequately justified belief in God’s possibility. The critiques of God’s coherence may not be decisive, and we could even grant that they are not convincing. Nonetheless this is insufficient to establish the rationality of belief in God’s possibility. There is still the question of the grounds for that judgement in the first place.
It could be that God is incoherent, but for reasons beyond our ability to grasp. In that case, the same limitations may explain both why the concept seems initially plausible, and also why objections failed to discredit it.
Plantinga would concede this, but still thinks that despite our limitations it can still be rational to believe God is coherent. But we can press the objection beyond merely saying there could be incoherence beyond our grasp. We can argue that there is reason to doubt the reliability of our modal judgements in the case of the particular demands imposed by the concept of God.
Van Inwagen questions whether our competence in judging familiar possibilities extends to exceptional metaphysical cases, including the possibility of a perfect being. He compares this with estimating distances by eye. This capacity works reasonably well in familiar circumstances, but can become unreliable when extended beyond them. E.g., we can reasonably judge how far away a bus might be, but not how far away the moon or sun is.
In ordinary cases, we judge what is possible by experience of actual things and their properties, or by their similarities to other observed things. Experience acquaints us with limited human attributes of power and knowledge. But in God such attributes extend infinitely. Rational acceptance of God’s possibility requires adequate grounds for believing these attributes could be extended infinitely, and for them to then co-exist in a necessarily existent being. We can have an intellectual concept of what is meant by such ideas, but that does not by itself justify believing that they really could exist, let alone co-exist.
Plantinga needs to show these grounds for doubt are misplaced, or supply positive grounds for accepting God’s coherence sufficient to counterbalance their weight. So, Plantinga draws too much reassurance from the inadequacy of critiques of God’s coherence. Without adequate grounds for either possibility or impossibility, and with Van Inwagen’s reasons to doubt our judgement, the only rational attitude is to suspend judgement.
Theis exposes a structural tension in the ontological argument. The nature attributed to God both gives its modal inference its power and impedes justification of its possibility premise. Necessary existence enables the inference from the possibility of such a being to its actuality. Yet the argument requires a priori reflection to shoulder the burden of justifying a judgement about a being radically unlike those that support our ordinary modal judgements. The reflection considered by Plantinga has not supplied adequate grounds for trusting that judgement.
The defenses of the ontological argument against Gaunilo and Kant aimed to show critics underestimated God’s unique status, only serve to further intensify the difficulty in justifying belief in the possibility of God.
So we don’t need to go as far as Hume in rejecting necessary existence as having no consistent meaning. We can understand that necessary existence means excluding every possibility of non-existence, while judging that we lack sufficient rational grounds for believing that anything could satisfy that description. We are therefore not rationally justified in accepting the possibility premise a priori, or therefore the existence of God.
Reference list
Anselm. “Proslogium.” In St. Anselm: Proslogium; Monologium; An Appendix in Behalf of the Fool by Gaunilon; and Cur Deus Homo, translated by Sidney Norton Deane. Chicago: Open Court, 1903. Originally written 1077–78.
Gaunilo of Marmoutiers. “In Behalf of the Fool.” In Proslogium; Monologium; An Appendix in Behalf of the Fool by Gaunilon; and Cur Deus Homo, translated by Sidney Norton Deane, 145–53. Chicago: Open Court, 1903. Originally written 1079.
Anselm. (ca. 1079) 1998. “Reply to Gaunilo.” Translated by M. J. Charlesworth. In Anselm of Canterbury: The Major Works, edited by Brian Davies and G. R. Evans, 111–22. Oxford: Oxford University Press.
Descartes, René. “Meditations on First Philosophy.” In The Philosophical Writings of Descartes, vol. 2, translated by John Cottingham, Robert Stoothoff, and Dugald Murdoch. Cambridge: Cambridge University Press, 1984. Originally published 1641.
Hume, David. Dialogues Concerning Natural Religion. 1779. Hume Texts Online. https://davidhume.org/texts/d/.
Kant, Immanuel. Critique of Pure Reason. Translated and edited by Paul Guyer and Allen W. Wood. Cambridge: Cambridge University Press, 1998. Originally published 1781.
Bibliography: Russell, Bertrand. A History of Western Philosophy. New York: Simon and Schuster, 1945.
Malcolm, Norman. “Anselm’s Ontological Arguments.” The Philosophical Review 69, no. 1 (1960): 41–62. https://doi.org/10.2307/2182266.
Plantinga, Alvin. The Nature of Necessity. Oxford: Clarendon Press, 1974.
Charles Hartshorne, “John Hick on Logical and Ontological Necessity,” Religious Studies 13, no. 2 (1977): 161.