Atheism and agnosticism: a primer

Writing a short primer on atheism and agnosticism feels a bit like watching a two-minute YouTube vid on how to milk rattle snake venom. The entry-level information may be on point, but one can’t help but think that more detail might be quite useful.

So, right up front I think it’s probably good to be clear. This primer is going to give you “the gist” of atheism and agnosticism. It’ll give you some useful handles on the key concepts. For those wishing to delve deeper, we’ll do our best to link out to a few revealing conversation threads and online resources.

So, without any further ado, let’s crack on shall we?

A few basic definitions

What is an atheist?

An atheist does not believe that any god exists. That’s really all there is to it.

The more complicated part of understanding atheism is not so much what it is but what it isn’t. There’s a ton of extraneous and inaccurate characteristics you’ll find attached to the atheist label. For example, atheists are frequently characterized as outspoken, argumentative, nihilistic, amoral and unemotional. Any of these adjectives could be true of an atheist. They could also be true of a religious person.

None of these extra add-on ideas are inherent to what it means to be an atheist. You could easily meet (probably already have met) an atheist who is quiet, obliging, hopeful, moral and deeply emotional. They may even like puppies.

Now, here’s where we hit the first patch of conceptual stickiness. People can and do debate in great depth exactly what conditions need to be met in order for an entity to be godlike. It’s a fun and curious tunnel of discourse to wander down if you feel so inclined on a rainy Sunday afternoon. Here’s a good link.

What is an agnostic?

An agnostic is anyone who does not claim to know if any god exists.

The key differentiating idea here is that agnosticism is about what a person claims to know, while atheism is about what a person believes. Again, the basic idea is of agnosticism is pretty easily grasped.

Just as we encountered with atheism, there are value judgments and misconceptions surrounding agnosticism to be wary of. Agnosticism is frequently superficially characterized as the Diet Coke of atheism. It has the connotation of being a relatively ‘open minded’ position and less hostile to a theistic position. An agnostic is also often thought of as someone who is simply undecided and more open to belief in a god, despite the presence of doubt. None of these characterizations are an inherent part of what makes a person an agnostic. The only criteria that needs to be satisfied to make someone agnostic is that they do not know if any god exists.

Which leads us to our next conceptual rabbit hole. There is a “loose” and a more stringent flavor of agnosticism. A foot loose and fancy-free agnostic simply claims to have no personal knowledge that a god exists. The more stringent version of agnosticism holds that it is objectively unknowable if a god exists. In other words, the stricter agnostic holds that no-one can know whether or not there is a god.

Are atheism and agnosticism mutually exclusive?

A common understanding of atheism and agnosticism is that the ideas are mutually exclusive. “Are you atheist or agnostic?” is the classic question belying this mistaken assumption.

It doesn’t take advanced qualifications in logic to see that there’s a bit of a problem with this notion of mutual exclusivity when it comes to the concepts of atheism and agnosticism. Once the various commonly held but false assumptions about both positions are swept aside, there is no reason to understand these ideas as being opposed to one another.

In fact, there’s no reason why someone cannot lay claim to being both agnostic and atheist. There are permutations of a/gnosticism and a/theism with which a person may identify.

Getting more specific

Agnostic atheist

An agnostic atheist has two positions. Firstly, they do not know for sure if any god exists. That’s the agnostic part. Secondly, they do not believe in any god. That’s the atheist component.

This might sound unusual or contradictory at first glance but when you swap god out for a ham sandwich the coexistence of these positions makes more sense. You may not know for sure if a ham sandwich is currently hidden somewhere in the room you’re sitting in right now (as part of some elaborate snack heist). However, the chances are you firmly believe that there is no ham sandwich in the room. If evidence of ham sandwich presented itself (such as a trail of mustard leading to a sofa cushion) you may revise your knowledge or your belief.

An agnostic atheist may say something like, “I don’t believe in a god. However, the universe is a big place. Maybe my belief is wrong. If someone could show me proof of god I’d change my belief.”

An agnostic may theoretically be open to believing in god at some hypothetical point in the future if someone were to provide evidence of their existence.

Gnostic atheist

A gnostic atheist also has two belief positions. There’s the atheist part in which they don’t believe in the existence of any gods. Then there’s the gnostic position which means they believe it is possible to know, irrefutably, that no gods exist (or at the very least they claim to know that personally).

Typically, a gnostic atheist’s worldview is informed by a strong alignment with scientific principles. This flavor of gnostic atheist may say something like, “We can look at the universe and attribute everything we see to science. Everything we know about science precludes the possibility of an omniscient and omnipresent consciousness. I therefore know god does not exist.” The nonexistence of a god can be known through observable and provable scientific laws governing the universe.

So, for the gnostic atheist, the hidden, hypothetical sandwich in the room is a yeti sandwich in chupacabra sauce. The gnostic atheist knows the sandwich is not there because it’s made of something which they are positive can’t exist.

Interestingly, a gnostic atheist may have very specific reasons for their knowledge claims, directed at specific religions. For instance, such a person may state that they know a religious text is false because the alleged deity’s exploits contradict the laws of physics.

Agnostic theist

Then we move into the theistic belief systems. A theist believes in the existence of a god. An agnostic theist would also hold that they nevertheless cannot know irrefutably and with complete certainty that their god exists. They believe but they do not know.

This whole business of believing something without any claim to knowledge might seem a very peculiar position to those rational types who conceptualize a “belief” as the natural result of knowledge. How can one possess an ironclad belief, such a person might ask, if this believer isn’t also able to claim to know that a god exists?

It’s worth noting that some religious belief systems don’t just accept belief without knowledge, they enshrine this state as a virtue. These religions (many flavors of Christianity among them) foster the notion that faith in the existence of a god is a fundamental tenet and a means of obtaining spiritual worthiness. From this perspective, having access to solid proof of the existence of god would (perhaps ironically) undermine the virtue of faith.

Gnostic theist

This comparatively straightforward position requires that two conditions be met. Firstly, a belief in the existence of a god and secondly (and somewhat redundantly) a conviction that the existence of a deity can be knowable.

For most gnostic theists, the distinction between belief and knowledge would be fairly trivial. The position of knowledge is simply a natural extension of having the belief.

Other definitions that make things just a bit more fun / complicated (funplicated).

Then we have some additional levels of granularity, just to keep life interesting. These descriptors don’t sit on the continuum of atheist to theist or agnostic to gnostic. They are more modifiers to provide additional information about a person’s position.


On top of a lack of belief in the existence of any deity, an antitheist believes that the notion of deity is damaging to society and humanity. It is a position of active opposition to religion and a religious worldview.

A typical expression of the position is informed by a perception that religion institutionalizes a host of harmful ideologies, such as misogyny, environmental destruction, xenophobia and racial intolerance. For an elegant articulation of antitheism, click here (popcorn recommended).

Misotheist / Maltheist and Dystheist

Misotheism (a.k.a. maltheism) is the theistic version of antitheism. That is to say, a misotheist believes in a deity or deities but also believes that these entities, and the religious institutions they spawn, are damaging to humanity. Dystheism is the belief that god is not omnibenevolent and may actually be a malevolent being. None of these “isms” offer a particularly upbeat take on the universe.


Then you have the delightful moniker, apatheist. Apatheism is probably more accurately defined as an attitude than a belief system and can be defined simply as a profound lack of interest in whether or not a god exists. While atheists are probably more likely to end up in the apatheist camp, it’s interesting to note that theists may also gravitate to this position. So perhaps apathy is the ultimate, swampy common ground we can all aspire to.


The concepts described in this primer aren’t intended to place limits on what people believe and why. They’re handles. They are ways to more readily grasp hold of abstraction. They are also, hopefully, constructive ways to begin a conversation about belief (or lack of it). Labels do have their limitations but at least it’s a place to begin.

About the author

Mark LambertMark Lambert worked for over 15 years in international development, during which he traveled the world and became slightly odd. Today he writes about technology, public health and society.

Follow Mark on twitter @Trebmalkram

Find more articles by Mark here

Share this article:
Email Print Facebook Twitter Google LinkedIn Pinterest Reddit StumbleUpon VK

Browse more articles