By Paul So
Philosophy of Religion is not my cup of tea, but still I have noticed that there is a tendency among many atheists to define their view as either (1) lacking belief in the existence of God or (2) believing that the existence of God is improbable. As an atheist, I can understand where they are coming from; they want to avoid the accusation that atheism commits them to a very extreme and dogmatic claim that they know with absolute certainty that God doesn’t exist. If you claim to know that God doesn’t exist, you carry a significant burden of proof to show that you’re right. I think there is something going significantly wrong here.
People seem to be conflating an epistemic claim with a metaphysical claim. An epistemic claim is any claim about one’s knowledge, or lack thereof, such as “I know that Pluto exists because of such and such evidence.” A metaphysical claim is any claim about reality regardless of one’s epistemic standing, like this one: “there are abstract objects beyond spacetime.” Obviously metaphysical claims do not need to be so extravagant. They can be downright boring (though non-trivial) like the claim that composite objects exist, or quite common yet controversial like “Fetuses are persons.”
Atheism is the metaphysical view that God does not exist, but, again, that claim alone does not entail any epistemic claim about the existence of God. It has less to do with one’s cognitive state (e.g. I lack a belief, I doubt, I disbelieve X, etc…) and more to do with the status of the claim. This seems clear given the fact that we could find an atheist who is convinced there is some logical proof against the existence of God, another who thinks that there’s a strong reason (if not irrefutable proof) against the existence of God, and we could even find an idiosyncratic atheist who believes by faith that there is no God.
But obviously there is much controversy over the epistemic standing of atheists. This is probably because most atheists are committed to the rules of rational discourse. As such, they recognize that anyone who makes a non-trivial claim has to provide some justification for it.
Atheists can vary on which kind of epistemic justification they consider to be sufficient for their conclusion. Some atheists are absolutely certain that God doesn’t exist. Such atheists will often say something to the effect that the notion of god is a priori conceptually incoherent. If the concept of X is logically incoherent, it is logically impossible for X to exist, like a square-circle. Some atheists claim that the notion of God is similarly incoherent, like Michael Martin, who has argued that God cannot be virtuous and omnipotent because cultivating virtues requires that one endure hardship or obstacles which are overcome with effort. Since there cannot be a being who is virtuous and omnipotent, God does not exist. This may not be the most impressive argument, but it is a nice little sample of a kind of justification for why someone might deny theism.
There are other atheists who appeal to a posteriori justification. Many of them would believe that the presence of suffering is evidence against the existence of God. If there is suffering, it is very unlikely that an all powerful, all loving, and all knowing God exists. Since there is suffering, it is very unlikely that God exists. They have found that there is some observable phenomenon that is incompatible with the claim that God exists.
I suspect one main worry is that in the end, when atheists provide any epistemic justification that God does not exist, they come across as claiming that they know God doesn’t exist. To claim that one knows something, one seems to be making a claim to infallible knowledge. But being an infallibilist about one’s knowledge of such and such implies that one has indefeasible justification for such and such. One’s justification for their belief cannot be undermined in the face of any contrary evidence.
Atheists clearly do not have to be infallibilists. Their reasons can be revised when there are better reasons. Just because their justifications are defeasible in principle, it doesn’t follow that it is easy to revise them. One still needs to find a strong justification that is difficult to counter in practice. According to this fallibilist picture, one doesn’t automatically claim 100% certainty when one provides an epistemic justification as long as it is defeasible (at least in principle).
The overall point I’m trying to make is that atheism is not merely an epistemic claim: it is not an absence of belief, presence of belief, etc. It is a metaphysical claim about the world that God doesn’t exist. But assuming that someone cares about the rules of rational inquiry, there is a variety of different justifications one could provide for that conclusion. Some justifications are a priori, others are a posteriori, and one isn’t committed to either one of these simply because they are an atheist. If you use both, you’re what I call an opportunistic atheist.
One of the implications of my conception of Atheism is that since it is a negative metaphysical view, it is irrelevant to contrast it with Agnosticism. Agnosticism is not a metaphysical view, but rather an epistemic view about God. It simply states a lack of knowledge because one lacks any epistemic strategy. Usually, an agnostic thinks there is no satisfying epistemic strategy to justify either Theism or Atheism. However, it is possible to be an agnostic atheist insofar as you hold the metaphysical view that God does not exist, but you lack any epistemic justification. A plausible version of agnostic atheism may argue that you don’t need an epistemic justification anymore than you need it for Russell’s teacup. The burden of proof somehow falls on Theists. But once you provide an epistemic justification for your metaphysical view, you are no longer an agnostic. Providing some kind of epistemic justification indicates that in some sense (whether in a fallible or infallible manner) you know that God doesn’t exist.
This is the conceptual terrain of Atheism. If you are an atheist, there is a wide range of epistemic strategies you can use to support your negative metaphysical view. You can claim with absolute certainty that God doesn’t exist by appealing to a priori justification (infalliblist atheist). You can claim that beyond reasonable doubt (not absolute certainty) God doesn’t exist by appealing to strong a posteriori justification (fallibilist atheist). You can be opportunistic by using any available strategy (opportunistic atheist), or you can refuse to subscribe to any epistemic strategy because the burden of proof is on theism (agnostic atheist). Atheism doesn’t have to be dogmatic, extreme, or rigid. It can be relatively flexible in allowing people to choose any epistemic strategy (or lack thereof). That isn’t to say this is a free epistemic buffet with all meals available. There are trade offs and problems for each epistemic strategy. For any one you choose, a theist can find a counter strategy (and vice versa). If you are an atheist, it is really up to you to decide which one you think might work.