(That literally happened to me one time.) Ok, this joke still needs writing, and that’s not my thing. But I do want to try and tease out a related conversational knot that’s been giving me trouble. In short, the knot involves the answers to the following questions:

• What does it mean to be an atheist?
• What does it mean to be a theist?
• What does it mean to be an agnostic?

Why does this matter? Because labels matter to us. If someone called me a “feminist,” my reaction might depend on what they mean by the term. If it just means “someone who advocates for the complete social, economic, and political equality of the sexes,” then I’m happy to carry the label. But if they mean it pejoratively to mean “someone who hates men and wants women to take over the world,” then I’m going have a problem with that. So which is the correct definition of feminist?

Similarly, if someone calls you an atheist, what exactly does that mean? You might accept the term when defined a certain way, but not when defined in another way. Also, if I say something like, “atheism is irrational,” the reasonableness (or truth) of that claim depends on the definition being used. If it means, “someone who knows with certainty that no gods exist,” then few people will accept the label, and rightly so.

What I want to do here is compare two approaches to defining these terms, and explain why I recommend one over the other. I’ll start with what I call the “four quadrants” model.

The Four Quadrants Model

Some people propose we renovate these terms (atheist, agnostic, theist) a bit to make things clearer and avoid foisting burdensome views upon others. Here is the renovation proposal:

There is a certain elegance and symmetry to this model. You have ‘theism’ and ‘a-theism’ juxtaposed with ‘gnostic’ and ‘a-gnostic.’ Very nice.

This “quadrant model” carries other advantages as well. First, it takes some pressure off of atheists who don’t want to claim that they “know” there are no gods. Second, it also takes pressure off of theists in exactly the same way. Third, it uses the term ‘agnostic’ in a way more true to the original meaning of the Greek word. In ancient Greek, ‘gnosis’ means ‘knowledge’ and the prefix ‘a’ mean ‘without’ or negation. So, to say that I am “agnostic” literally means “I don’t know.”

Cons of the Quadrant Model

Unfortunately, there are some drawbacks to this model. For one, the unconventional use of ‘gnostic’ and ‘agnostic.’ While I do love etymologies (word origins), most people find them rather pedantic. The simple truth about language is that meanings change over time. A word gets it’s meaning from usage. If we were arguing about what technical term philosophers should use, that might be a different story. But if we want an ordinary term for common usage, it is simpler to use the word conventionally. So, when it come to ‘agnostic,’ most people understand this to describe someone who is undecided about God’s existence. And when it comes to ‘gnostic,’ this term refers to followers of an religion that revolves around the possession of esoteric, mystical knowledge (Gnosticism). For Christians, this is especially important, because ‘gnostic’ carries a heavy negative connotation, and has for thousands of years. To be a “gnostic theist” is to be a heretic, for most Christians. So, shifting meanings in this way muddies the waters.

Secondly, this model suggests that knowledge and belief are like height and width–two separate dimensions of thought. But belief and knowledge relate more like acceleration and force. Belief is a component of knowledge, just as acceleration is a component of force (F = ma). So it is misleading to represent them on two perpendicular axes.

This quadrant model also fails to provide a safe conceptual space for the truly undecided. True undecidedness is a real position on many important questions, including scientific ones. In numerous cases (e.g., the multiverse), the most rational thing to say is “I neither believe there is an X, nor do I believe there is not an X.” But the diagram above tells me that I must pick a quadrant.  I must either believe (the space below the ‘x’ axis) or not believe (the space above the ‘x’ axis). If we revised it to allow people to be on the axis, perhaps right at (0,0), then what do we call them? There is no in-between because the model is binary in principle.

Finally, the fellow in the upper-left quadrant confuses a few things. He wants to say “I don’t believe any god exists,” but he also wants to say “I’m not CLAIMING that–I might be wrong.” I understand the discomfort here. He doesn’t want to make a strong claim, because that would require a strong defense, which is a burden he doesn’t want. Fair enough. But he isn’t like a helicopter that has yet to land. He has landed, even if tentatively. He thinks there are no gods. He’s not saying he is certain, or that he can prove anything, he is simply describing where he has landed. And he admits that he may have landed on the wrong spot. That’s fine. But even a tentative landing represents a claim about what you think is true about the universe. I’ll say a bit more beloe about the the difference between “having no belief about p” and “not believing p.”

The Sliding-Scale Model

Instead of a binary-based model, and the restrictions that entails, I prefer a sliding-scale approach.  This non-binary model allows for a wide range of possibilities, grouped into three natural categories. Rather than being forced to choose from only four possible positions, people can personalize their position based on their beliefs and confidence level.

I didn’t have a cute graphic for mine, so I made this:

On this view, you can be anywhere between 0-100% confidence about a certain idea or claim. (“p” refers to any claim, or proposition, like “God exists.”) If you find yourself hovering around the 50% mark, we’ll say you neither believe it nor disbelieve it. This is where we should fall on claims like “this fair coin will land on heads when flipped.” Sometimes we say things, loosely, like “I don’t know.” But this conversationally implies that we simply don’t have a belief one way or the other.

If you land roughly between 65-100% confident that p, then you clearly believe it is true.  At 100% confidence, you have no doubts and think there is no chance that p is false. (Notice that we’re saying nothing about knowledge here. This is only about beliefs, just to keep things simple and clear.)  If you fall anywhere in between 0-35%, you think that p is false, though the closer you get to 50%, the more you lean toward thinking there’s some chance it could be true. For example, suppose I’m looking over a balcony, wondering if I could jump safely into the pool. I give myself about a 15% chance of plunging safely into the water. So, if you ask me, “Do you believe you can make it?” I’d say, “no.”  If you have 0% confidence that p, then you have no doubt it is false–you disbelieve it with maximum confidence of its falsehood.

The Sliding-scale & God

Now, if we apply this to our debate about definitions, here’s how I think it works in terms of belief about God. If you have ~65% or more confidence that God exists, then you believe that God exists and we call you a theist.  (I think most of us agree with that.) But theists, like atheists, can possess little or much confidence. If you are ~35% or less confident that God exists, then you disbelieve that God exists and we call you an atheist. (Nothing about knowledge here!)

Both segments (red and green) of the scale represent a “belief state,” two sides of the same coin.

But that’s ok because merely believing or disbelieving that p doesn’t saddle you with an undue burden. I call them both belief states because disbelieving that p is roughly synonymous with believing that p is false. I.e., “I disbelieve that God exists” is the same as “I believe there is no God.” It’s like someone saying, “I don’t think the coin will be heads”– you wouldn’t need to ask whether they believe it will be tails. It’s just a belief! No big deal. Whether it is rational or whether you know is a different ball game and will require more justification. But the atheist need not attain certainty or prove there is no God in order to be a rational atheist.

Questions & Concerns

Some atheists prefer the quadrant model because they are more comfortable saying “I don’t have a belief about God–I lack belief in God.” But saying you lack a belief about God’s existence is not accurate. Atheists lack an affirmation of God’s existence, but they have a belief state (doxastic attitude), and that belief state is disbelief. They take the claim “God exists” to be false. If you don’t take it to be false, then you are either undecided or a theist. The only people who truly lack a belief about God are those who have never considered God’s existence, like my dog Duke or my friend’s baby. They just have no belief state about God whatsoever.

What about agnostics? Now, I admit that the term ‘agnostic’ as a label for the undecided is somewhat regrettable, given the literal Greek meaning. Coined by Thomas Huxley in the late 19th century, the term served to contrast his position against those who felt they had attained “gnosis” or knowledge of answers to the big questions. Huxley used the term to express either skepticism or humility or both. But regardless of Huxley’s intentions, the term now refers to someone who is undecided on a matter, religious or otherwise. For now, it works. Launch a campaign to shift the usage if you dislike it, but it isn’t quite right to tell people that they’re using it wrong now.

To avoid mixing up atheism and agnosticism, note that the claim “I don’t believe that any gods exist” (as in the four quadrant graphic above) can mean several different things. Consider the claim E: “the number of stars in the universe is even.” If I say that “I don’t believe E,” that could mean: (1) I think E is false, which implies that I hold the odd-number-stars view; or (2) I don’t believe E, but I don’t think it’s false either. I’m just undecided, or agnostic on the matter. So when you want to express atheism and NOT agnosticism, it is better to say something like, “I believe there are no gods,” or more simply “I disbelieve theism.”

If you discover that the belief-state you are in is difficult to defend, welcome to the club! Each position has its unique challenges and weaknesses. There’s no problem with redefining your position in order to make it more defensible, as long as the changes are not “Ad hoc” and the new definition is coherent and unconfusing.