This is a bit of a heavy one, and it’s a topic that’s very important to me. If you want to talk about it more, please email me, there’s a contact tab at the top of the page. Don’t clutter up the comments section with your attempts at dismissive one-liners. This is some serious shit I’m getting into here. Consider yourself warned.
David Eagleman is a possibilian. If you’ve never heard the word before, it’s because it’s a stupid word. Here’s how Eagleman introduces the concept.
While there are plenty of good books by scientist-atheists, they sometimes under-emphasise the main lesson from science: that our knowledge is vastly outstripped by our ignorance. For me, a life in science prompts awe and exploration over dogmatism.
Well yes. That’s the point of science. As Dara O’Briain so nicely put it, “Science knows it doesn’t know everything. Otherwise, it’d stop.” What Eagleman’s trying to say here is that prominent scientist-atheists like Richard Dawkins, Sam Harris, and Daniel Dennett are arrogant, refusing to acknowledge the vast amount of knowledge we have yet to come by.
Apparently Eagleman hasn’t read any of these people’s books. In The God Delusion, Dawkins talks deeply about how all of humanity’s relatively insignificant knowledge about the universe was hard-won, and how religions are arrogant for claiming to know everything about everything (which they do claim). And Harris and Dennett are the same way. But let’s move on.
Given these considerations, I do not call myself an atheist. I don’t feel that I have enough data to firmly rule out other interesting possibilities. On the other hand, I do not subscribe to any religion. Traditional religious stories can be beautiful and often crystallise hard-won wisdom – but it is hardly a challenge to poke holes in them.
So you don’t subscribe to religions, but you’re not an atheist. You do know that’s what atheist means, right?

An atheist is someone who doesn’t believe in god. That’s it. That’s really all there is to it. There are a massive number of misconceptions about atheist agendas, but really the only thing we have in common is not believing in god.
Eagleman, on the other hand, doesn’t want to commit to atheism, because he thinks there’s something to commit to.
So it seems we know too little to commit to strict atheism, and too much to commit to any religion. Given this, I am often surprised by the number of people who seem to possess total certainty about their position. I know a lot of atheists who seethe at the idea of religion, and religious followers who seethe at the idea of atheism – but neither group is bothering with more interesting ideas. They make their impassioned arguments as though the God versus no-God dichotomy were enough for a modern discussion.
All right, you’re not making sense. Atheists seethe not at the idea of religion, but at the effects. If you live your life as a Christian, but it doesn’t inform a single decision you make, we don’t care. And religious people seethe at atheists because they see our very existence as insulting. It’s not a rational position.
And furthermore, the idea that atheists are, as a group, ignoring “more interesting ideas” is absurd. We’re skeptics, and many of us are scientists. We examine the world as it is, not how we imagine it could be. When evidence arises, it is taken into consideration.
But that last sentence is where I get really confused. We talk about the God/no God argument as though it’s enough because it is. It’s a binary argument. It’s not all there is to the world, but there is no middle ground. Even the arguments within it have a middle ground, like whether God created man, guided evolution, or whether evolution was unguided. But there either is a God, or there is not. There is no such thing as “kind of” a God. You can argue about what he does, where he lives, what he looks like, etc, but his existence is a yes or no question. It’s made out to be a black and white argument because it is.
But here’s where Eagleman loses all credibility entirely.
What if we were planted here by aliens? What if there are civilisations in spatial dimensions seven through nine? What if we are nodes in a vast, cosmic, computational device? Consider the enormous “possibility space” of stories that can be dreamed up. Take the entirety of the Judeo-Christian-Islamic tradition as a single point in this possibility space. The eastern religions are another point. Strict atheism is another point. Now think of the immense landscape of the points in between. Many of these points will contain stories that are crazy, silly, or merely wildly improbable. But in the absence of data, they can’t be ruled out of that space.
Yes, and what if Santa Claus is real? This is the problem with possibilianism.
Let me explain to you something called the Null Hypothesis. It is the default state of all scientific inquiry, and I only capitalize it because it’s really important. The Null Hypothesis essentially says that you can assume something is not true until evidence arises that it is. If you make a drug to treat headaches, you must assume that it does not work until you do the proper studies and find out that it does. If you think that the stars have an effect on your love life, you must assume that they do not until proven otherwise. And if you are going about your life and someone tells you that the universe and everything in it was created by a man who lives in the sky and whose son took the entire burden of the sins of mankind onto his shoulders and then died, leaving you to redeem him despite the fact that no one ever asked him to do that in the first place, then it’s only rational for you not to believe it until evidence arises that it is in fact true. Nothing should be accepted on faith.
And that’s where atheists come from. I hesitate to say that atheists are waiting for evidence, because that makes it sound like we want evidence that religious claims are true. Speaking for myself, I don’t. I want to know the truth about the universe. If the truth is that it was created by an intelligent being, then that’s fine, but if that’s not true, then I don’t want major political or educational decisions made on that basis.
It’s ok to say you don’t know, and that you can’t make a choice because there isn’t sufficient evidence, and that seems to be what Eagleman is driving at here, but the evidence is not neutral. The evidence is vastly stacked on the side of science, at a score of infinity to zero. I don’t think there are any intelligent atheists who would say that there definitely is not a god, and anyone who is sure of that is being as irrational as the most dogmatic of religious extremists. What we can say can be crystallized as follows:
That statement does not rule out the possibility of the supernatural. It makes no statement about the truth of falsehood of supernatural claims. It does not, as Eagleman puts it, “rule out other interesting possibilities.” But if there has never been evidence of something, why should we give it any credibility?
There has never been credible evidence of Santa Claus, so we don’t believe in him.
There has never been credible evidence of a tooth fairy, so we don’t believe in one.
There has never been credible evidence of an Easter Bunny, so we don’t believe in him either.
And so it goes for God. The certainty that atheists have is what I would call a practical certainty; we do not rule out the possibility of God, but we can act—for all intents and purposes—as though there is none.
So what does Eagleman propose?
This is why I call myself a “possibilian”. Possibilianism emphasises the active exploration of new, unconsidered notions. A possibilian is comfortable holding multiple ideas in mind and is not driven by the idea of fighting for a single, particular story. The key emphasis of possibilianism is to shine a flashlight around the possibility space. It is a plea not simply for open-mindedness, but for an active exploration of new ideas. Within the realm of what is addressable, we profitably apply logic to further knowledge. Possibilianism is “anything goes at first” – but we then use science to rule out parts of the possibility space, and often to rule in new parts.
But…that’s science. That’s what science does. Exploring new ideas, holding ideas in mind, looking around, applying knowledge and logic to rule out possibilities and open up new ones, those are all what science does.
Here’s the difference. Suggesting wild hypotheses like “maybe we were put here by aliens” or “maybe there are civilizations between the seventh and ninth dimensions” or “maybe our whole universe is in a raindrop in a bigger universe” is not scientific until you have some reason to believe those things are true. The big bang theory was treated as crazy when it first arose, but it arose based on evidence and it predicted more evidence that then, when looked for, was found exactly as predicted, so it was vindicated. You can’t just throw shit out there.
So possibilianism, to clarify, is the opinion that we should embrace all ideas, all possibilities, every point in possibility space, equally. Reject no explanation, close no door, burn no bridge.
And that opinion is wrong.
Nice post, and I agree completely.
One thing that I really take issue from Eagleman is the notion that religious silliness falls into the category of “interesting possibilities”. I can't imagine, for the life of me, how things that we know to be complete fucking fantasies qualify as “interesting possibilities”. Stories from Jewish, Christian, Islamic, or Hindu texts are treasures in the sense that they reveal a great deal about humanity's cultural history and can be interesting as literature. What myths people believed (or used metaphorically) is interesting. However, the notion that these myths are actually true isn't even remotely interesting or remotely possible.
His other options for “interesting possibilities” (such as the just-so alien story) would only be interesting if actual evidence supported them. Sure, that would be interesting – but it would also then fall into the realm of science.
As pointed in a recent post over on Jerry Coyne's blog, there really isn't any question than can't be objectively answered by science that can be answered by religion. It's a worthless method of inquiry (if it could even be called that).
I apologize if this should have gone into your contact section rather than in the comments.
No, that's an excellent comment. What I hate is stuff like “at least im not going to hell lol,” which is the kind of shit that crops up on this topic all the time. And yes, that's exactly my point. Not all ideas are worthy of equal consideration or respect, which is why the scientific community takes so damn long to change their minds about anything. You have to EARN the right to be taken seriously.
For example, string theory has been put forward and studied by some of the most brilliant minds in physics, but it doesn't predict any evidence and doesn't have any testable implications, so it's been pretty much ignored until it gets fleshed out more.