Atheism – What is it, Exactly?

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.


  1. Clear, concise taxonomy here. I once thought it important to make the metaphysical claim, that god doesn’t exist; but have since reconsidered that a bolder move than can be reasonably justified; so I now hold the more modest epistemic claim that the incoherency of the concept, coupled with the lack of evidence beyond doubtful testimony, really just means that there isn’t any reason to accept it – and no need for it in my personal experience.

    As I’ve also said elsewhere, strong theistic faith seems grounded in emotional experiences that I’ve never had (and no longer want), rather than rational thought-processes or their results.

    I may discuss the matter further in terms of an interesting aspect that occurs to me, worth mentioning here in passing: Traditional theology has always implicitly held that god is not only an existent entity, but a foundational principle of the universe, rather in the way some scientists hold that ‘causation’ is a principle we simply must be able to find in the universe. This may be why some New Atheists write of a ‘god hypothesis’ and why some believe science ‘disproves’ that ‘hypothesis,’ which somehow misses what such a foundational faith entails (a need for an answer to the unanswerable, perhaps?).

    It’s almost explicit in the “Prima Causa” argument. Somehow the universe can’t exist without ‘this’ per theologians, just as somehow it can’t exist ‘without ‘that,’ according to some scientists. Yet I find myself quite able to conceive the universe without either ‘this’ or ‘that,’ because the universe doesn’t seem to care much what we know or believe.


  2. Hi Paul,

    Good article and something I have thought about myself. When someone says that atheism is simply a lack of belief in God then I wonder how it differs from agnosticism.

    Incidentally, I doubt that any atheist would claim to be an infallibilist

    And of course a theist can also be a fallibilist, there is nothing about theism which entails that one must commit absolutely to it, although many religions ask this of their followers. But the theist with doubts is almost a cliche.

    Also, some versions of theism are a claim about the fundamental nature of reality and one is denying that claim then one is making a positive claim about the nature of reality – committing to at least some version of Naturalism.


  3. Paul

    “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.”

    You seem to be using the word ‘know’ in a non-standard way here (non-standard at least in terms of (my understanding of) ordinary usage).

    Generally I thought the piece was clearly argued, though I have a niggling doubt about the basic categories you are dealing with here. They seemed just a little too neat. Perhaps it is because you were basically explaining philosophical terms and categories (like ‘metaphysical’) and accepting them as given. Which is okay, so long as the categories themselves are seen as being in some sense provisional – valuable only to the extent that they might be useful for a specific purpose.


  4. Thanks for the clear review. For me, the analysis usually gets stuck at the question of what is god?

    This would seem to be a necessary first question. The existence or not of such an entity can then be rigorously evaluated. All theists probably have their own unique insights. Curiously, it is also necessary for an atheist to have a god conception before she could refute it. (Most atheists borrow their God concept from some familiar religion – not a particularly rigorous move.)

    Without a precise definition of the concept of ‘god’, debates about such will be extremely fuzzy.

    Liked by 1 person

  5. Hi Paul,

    Apparently my new phone lost my first attempted comment. Perhaps a deus in machina.

    Thanks for a clear review. I have, however, noticed that almost always god is discussed without a specific definition of what is meant or imagined. Even amongst religions, the object of their reverence is vague and mysterious. Atheists, curiously, seem to casually pick up the first available idea of god and then destroy it – another straw man bites the dust! 🙂

    Clearly, one should precisely define an entity first if one wants to test claims for its existence or reality, or otherwise. This is not possible, however, in the absence of information that can be rigorously evaluated. All putative information so far has fallen short, hence the need for faith. This is not completely surprising:

    My intuition is that god is the all, the source of everything, known and unknowable. This ineffable presence undergirds everything and can be felt by everyone, even everything, but has not been defined in narrative language*. Hence all the confusion.

    *I have this strange idea that science brings us closer to god!

    Liked by 1 person

  6. This is a topic that in the past has generated intense commentary. Like Liam, I found Paul’s discussion clear enough, except for my position as an agnostic in the sense of Thomas Huxley’s statement:

    “When I reached intellectual maturity, and began to ask myself whether I was an atheist, a theist, or a pantheist; a materialist or an idealist; a Christian or a freethinker, I found that the more I learned and reflected, the less ready was the answer; until at last I came to the conclusion that I had neither art nor part with any of these denominations, except the last. The one thing in which most of these good people were agreed was the one thing in which I differed from them. They were quite sure that they had attained a certain “gnosis”–had more or less successfully solved the problem of existence; while I was quite sure I had not, and had a pretty strong conviction that the problem was insoluble. And, with Hume and Kant on my side, I could not think myself presumptuous in holding fast by that opinion. . . .”

    So I’m disinclined to view my agnosticism as a form of atheism, though I appreciate Paul’s view that “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.”

    Outside of social media, I find most such discussions in my personal life accomplish little. Often, I feel compromised by the assumption that I’m a theist, but I no longer engage in such discussions unless some chance remark requires it. Most theists in my acquaintance are what I would describe as naive fideists. I do not discount faith-based accounts for someone’s theism because I’m interested in and open to their personal experiences, but remain skeptical of the simpler accounts that seem like little more than “Why/Because/Why/Because, etc.” exchanges.


  7. There is actually a fairly firm definition of God as believed in by the main monotheistic traditions.

    God is at least a necessarily existing intelligence which is the ultimate creator or source of all contingent things.

    Generally God is also taken as morally impeccable, omniscient and omnipotent.

    That may not be perfect, but it is a clearer and firmer definition than, say, Naturalism has.

    Liked by 1 person

  8. Robin, “a fairly firm definition of God . . . by the main monotheistic traditions” is not helpful to me personally, regardless of how one views it by comparison to “naturalism.” “Bachelors are unmarried men” is to many clearer and firmer than either of the various conceptualizations of God or naturalism. So what? The article focuses on unpacking atheism, not theism.


  9. Hi Thomas,

    I was responding to another poster, so if you think that questions as the the definition of God are not relevant to a discussion unpacking atheism then maybe you should address it to the person who made the original comment, not to the person who responded to it.


  10. If you say God does not exist you face the impossibility of proving a negative, not a difficulty.

    You are going down a dead end making a distinction between Metaphysics based on “belief” and Epistemic “knowledge”.

    You cannot say you “know” God does not exist, but you can say you “know” God personally, and therefore that God exists.

    You are also unclear. I say one’s cognitive state always determines the status of a belief or a knowledge claim.

    You eventually get back to the usual basic issue, proof of belief or knowledge. People who claim to know miracles by personal observation are difficult to deal with. various arguments will also apply to justify any belief.

    I am a lawyer. Perhaps you should have studied law if you want to get into problems of proof when you are not doing simple scientific experiments. Too much hubris by science about what it is doing and how it sets up what it is doing.

    It would be better if you just relied on paragraph 1, above, to say its a matter of belief to be tested unless you claim to personally know God, in which case we get into deep issue of mental states, which are the bases of claims.

    That seems clear enough. Read more here in my free work on skydrive page 171, or search the PDF using “God”


  11. Hi Marcus,

    It is not impossible to prove a negative. For example I can prove the non existence of a teapot orbiting Pluto which is inscribed with an algorithm to generate the binary expansion of a Chaitin Constant.


  12. Depends also on how absolute you want the proof to be. I think we can prove beyond reasonable doubt that the non existence of a maximally powerful, intelligent, knowledgeable and good being, to whom there would be any point in praying to alleviate suffering.


  13. Maybe also the non-existence of a place where I could be eternally happy in the knowledge that my siblings are experiencing the worst possible agony for eternity.

    Or the non-existence of a being who, in the knowledge that our only hope for avoiding eternal ruin rested in our believing a certain fact, didn’t drop just a few more clues to help us out in this.


  14. Belief in gods appears to be the default position; ancient Rome recognized thousands of gods. It still is fun to admire the magnificent artifacts remaining from those beliefs: temples, statues, churches. Philosophers at that time, however, began to actively question the foundations of the ‘theologians’.

    Modern atheists, using new tools, have built up a cottage industry of knocking down those ancient gods – an unfair battle to say the least, but necessary. However, atheism can only succeed fully if it has a formula for denying all possible gods. Such an a priori negative proof has not been presented and is unlikely in an environment of very limited information.

    Some modern theologians suggest that god is a metaphor for an ontology of everything. Each human is capable of confronting this ineffable reality through intuition, not through logic or reason. Many individuals have reported unusual episodes of ‘cosmic consciousness’, some interpreting this as god speaking to them directly. This may indeed be so. It all depends on the precise definition of god.

    It is also important to distinguish between a reasoned definition of god in an organized religion and a deep personal (emotional) experience that might be labeled as an awareness of god. The content of these latter experiences is highly contingent upon the cultural milieu, but they continually feed a social religious sensibility. In rare instances these experiences have resulted in global religions.


  15. Marcus,
    All I see are a series of unsupported assertions with no argument. I certainly encourage you to keep on going. Let me know how well you progress in developing a single argument with that kind of approach.

    You’re welcome. However, I’m not sure I see the problem about defining the term “God”. It’s true that many different people use the word “God” to mean different things, but in the context of philosophy of religion the word “God” just means a transcendent creator who is omnipotent, omniscient, omnipresent, and omnibenevolent. An atheist simply denies that such a being as described exists whereas theists believe such a being exists. There could be other god concepts like pantheism and panentheism, but much of the debate is focused on theism.

    Mark English,

    I didn’t know there’s a standard ordinary use of the term “know”. I often assumed that people use the word “know” in so many different ways (e.g. “I know how to ride a bicycle” (procedural knowledge), “You know what I’m sayin’?” (in this case, the person is asking if the listener understands anything he or she says or thinks))…presumably because natural language is a bit messy like that.


  16. Paul

    Of course the word ‘know’ can be used in different ways in different contexts.

    But if I provide some kind of reason or evidence for a claim, I don’t see how this implies or entails that I ‘know’ that my claim is correct.

    Let me try to explain how I understand the word when it is used in this sort of context. When used in first person form, ‘know’ implies certainty. When used in the third person (obviously by someone other than the knower) it generally implies that whatever the knower knows is accepted as being true by the speaker and usually by his interlocutors also. As in: “John knows that Mary is cheating on him.” Like, she is cheating on him and the speaker and his interlocutor(s) are aware of this fact (as well as John).

    It’s a small point. I follow the gist of the paragraph in question. Call it a distraction if you like.


  17. in the context of philosophy of religion the word “God” just means a transcendent creator who is omnipotent, omniscient, omnipresent, and omnibenevolent.

    I think my definition better captures what a theist means by the term. The claim is about the nature of all reality, not just about some being who happens to exist.


  18. For example Richard Dawkin’s “central argument” in “The God Delusion” presupposes a contingent being who just happens to exist. Hence theists tend to respond “I don’t believe in that kind of god either”.