I’ve been wanting to write down my thoughts on the subject of belief and truth for some while now. The distinction between the two is one of the cornerstones of how I see the world. A good theory of what the truth is, and what it means to have a belief has a profound impact on how we think about the world. It also has a profound impact on how we understand other peoples’ perception of the world.

The Truth:

The objective truth. The true truth. The truth is true even if you don’t believe it is true. It is true even if you don’t know it is true. It is true even if you can’t prove that it’s true.


A person’s perception of the truth. We form our beliefs based on a combination of several things, including our personal observations, our reasoning, and our prior beliefs. A belief might not be the objective truth, and it’s foolish to treat it as if it were. However, belief is how we experience the truth, so it’s the closest thing we have.

The role of evidence:

Many people equate evidence with truth. If you ask people to define objective truth, they will likely say something about evidence. Some people even treat an idea with no evidence in the same way they that they would treat an outright false idea, such as in the anecdote described in this post by David J. Balan.

Neil deGrasse Tyson has put out his own theory of “Objective Truth”. And his theory is all about evidence. 

According to Neil deGrasse Tyson, an idea becomes the Objective Truth only after it has been established by a substantial amount of evidence. This is a fine way to define objective truth, since if we want to be extremely sure that an idea is true, then we almost certainly need a strong body of evidence to prove it. However, I think it’s worthwhile to acknowledge that an idea can be true even if there is no evidence for it. If there’s no evidence, it can still be true, we just wouldn’t know it. 

Newton produced the proof for how gravity worked in the 1600s However, the equations that Newton came up with would have still worked at any prior period in history. They would even have worked if nobody had proven them. The evidence for Newton’s equations isn’t the thing that made them true. What the evidence did was allow us to be certain that they were true. Essentially, evidence is just a tool that we use to make sure that our beliefs are close to the truth.

Likewise, a thing can be untrue, even if there actually is evidence. What looks like good evidence can often be flawed. There are many examples of this in the criminal justice system.

One good example of this is the case of Ronald Cotton where eyewitness Jennifer Thompson famously misidentified the perpetrator.

She had never been so sure of anything.

His name was Ronald Cotton and he was the same age as she. Local man, headed down the wrong road, had already been in trouble with the law. He had been arrested on first-degree burglary charges and had served 18 months in prison for attempted sexual assault. Cotton had insisted that the relationship resulting in the assault charge was consensual and that he was being unfairly targeted by police because he liked to date white women.

When Thompson picked him out of the lineup, everyone was sure they had the right man.

Cotton is tall and handsome, with baby-smooth chocolate skin and a warm, engaging smile. Confronted by Thompson, his normal calm failed him. He was petrified. But he said nothing, betrayed no emotion.

Cotton’s actions and past hadn’t helped his case. He was nervous. He got his dates mixed up. His alibis didn’t check out. A piece of foam was missing from his shoe, similar to a piece found at the crime scene.

Not only was Cotton identified by the primary eyewitness, but there was other evidence too. There was physical evidence regarding the foam on his shoe. He couldn’t keep his story straight. He had past convictions for sexual assault. There was a lot of evidence that suggested he did it, and it was pretty compelling. 

However, DNA Evidence showed that Cotton couldn’t possibly have been the rapist.

Cotton was unsuccessful overturning his conviction in several appeals. But in the spring of 1995, his case was given a major break: the Burlington Police Department turned over all evidence, which included the assailant’s semen for DNA testing, to the defense.

The samples from one victim were tested and showed no match to Cotton. At the defense’s request, the results were sent to the State Bureau of Investigation’s DNA database and the database showed a match with the convict who had earlier confessed to the crime to a fellow inmate in prison.

Evidence is not synonymous with truth, and even if you have evidence for something, that doesn’t necessarily mean that it’s true. There could be a mistake in the evidence, or there could even be a nuance that you haven’t thought of.

My Truth? Your Truth? His Truth? Her Truth?

One concept that occasionally comes up in online discourse is the idea of a person having their own truth. Most of the time when you see it, someone “telling their truth” is portrayed as a positive thing. But when a post is specifically about what a person’s truth actually means, it usually ends up saying something to the effect of “there is no her truth or his truth. There is only the truth”

Take the following comic for example:


This is a widely circulated comic online, and it contains 2 people expressing different beliefs about what number is drawn on the ground. They state these beliefs as though they are the truth, and there is a caption below in black font that implies that both of their beliefs are valid. 

Then apparently, someone altered the comic, crossed out the black text, and added their own text in red. This red text assumes that both of the characters are “uninformed” and that at least one of them is definitely wrong. It goes on to say that they should have checked the facts, that they don’t want to do any research, and that what they’re doing is ruining the world. 

I think that the person who wrote the black text, knows best what that symbol is supposed to be. That person is presumably the original author of the comic, and the person who created the symbol in the first place. I can’t think of a way any other person can possibly know better what the symbol is supposed to be. Apparently, according to that person, both 6 and 9 are right, and if that’s true, then the red text seems very silly. 

Furthermore, this the symbol in this comic is a metaphor for much more complicated questions in real life. With real-life versions of this dilemma you don’t always have an obvious alternative explanation for what the truth might be. You just see a 6 and already know about ‘9’. In real life, both sides might be incredibly informed, and the reason they disagree might be because the problem is so complex that each party doesn’t have all the information the other party has, or they might have made a mistake in their reasoning.

They may even have seen what appears to them to be 100% conclusive evidence. However, one or both of them might have misinterpreted something along the way. They can’t reasonably be expected to know about the mistake. If they did, then they would have already gone back and fixed their reasoning. To them, their side is the Objective Truth.

It could also be the case that all their facts are both totally true, and the reason they disagree is because they’re not seeing the bigger picture. They might not even know about a bigger picture. It’s not always obvious where one exists.


I prefer this other widely-circulated image. It covers some important nuance that the above comic (the original version) doesn’t.

The core problem is that belief is how a person experiences truth. You can’t tell the difference between a strongly-held, but false belief and the truth. If you could, then you wouldn’t have the false belief in the first place. You can’t expect other people to tell the difference either. To them, it is the truth! This is what “their truth” actually is. Humans don’t have some sort of mystical “truth-sense” that lets us know for sure what the truth is. It’s not so easy to just choose objective truth over your truth, when “your truth” is the very way that you experience truth.

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14 comments, sorted by Click to highlight new comments since: Today at 6:00 AM

However, I think it’s worthwhile to acknowledge that an idea can be true even if there is no evidence for it. If there’s no evidence, it can still be true, we just wouldn’t know it.

Bearing in mind that evidence is only one kind of justification, that's just a reinvention of the old idea that justification and truth are distinct. In general, it's not clear why you are addressing the subject by way of memes and celebrities rather than philosophical tradition.

Based on your comment, it seems like you are making a value judgement that philosophical tradition > memes & celebrities, and that reinvention is not worthwhile. But I don't see how "reinvention" is a bad thing, nor why philosophical tradition should be valued more than this version using memes & celebrities. 

Memes and celebrities are often easier to understand than philosophical essays. If reinvention gets more people exposed to the same (good) thing, then it has more opportunity to spread. Doesn't matter if it's something that's been said before, in my view; this piece is well-written and does a good job propagating these ideas forward, to take root more firmly in the collective unconscious.

If reinvention gets more people exposed to the same (good) thing, then it has more opportunity to spread.

But we don't know that it is the same or equally good -- that is a crux. We don't know that the OP already has a mainstream understanding of epistemology, because they didn't say whether they are explaining or reinventing (although the vibe is more the latter).

Based on your comment, it seems like you are making a value judgement that philosophical tradition > memes & celebrities, and that reinvention is not worthwhile.

Philosophical tradition is very likely to be better, since it is more people and smarter people doing something a longer period of time; similarly, reinvention of something complex is unlikely to be an improvement.

You say "value judgement" , but it's not 50:50.

I distill this down to a pretty simple statement: truth/true is external to the mind while beliefs are internal to the mind. Is that a good bumper sticker type summary?

BTW, related to the last image, have you read The Flatlands? If not, you might find it has some insights for you thinking here.

Yeah, that's essentially it.  I also tried to emphasize the idea that we can't 100% reliably know the truth because we can't perceive truth directly, only indirectly through our senses and reason.

And regarding The Flatlands, do you mean this:  https://www.amazon.com/Flatland-Romance-Dimensions-Edwin-Abbott/dp/B0875SRH84/

Yes, that book/monograph.

Also, and this perhaps the idea I was most trying to get across, we can't know when out belief differs from the truth because our belief is the way we experience truth.  

I appreciate the effort, but I'm not sure this is a good fit for LessWrong.  It seems to be using "truth" and "belief" in ways that aren't formally defined, and doesn't seem to be aware of Bayes' Rule or direct math treatments of evidence and uncertainty.  

I can't tell, but it feels a bit like a prelude to some motte-and-bailey about "truth" being applied to models and generalizations, which are neither true nor false in any rigorous sense, only applicable or useful in some cases.

I'm afraid I don't quite understand what you're getting at. 

I know what Bayes' Rule is, but I'm not sure how it applies to this post.  I tried to mostly stick to abstract ideas of truth and perception of truth, and I didn't really get very deep into any real examples which you might want to actually measure and statistically analyze.

I'm also not sure where you're getting this sense of a pending Motte and Baily from.  You mentioned something about models that are neither true nor false, but that didn't give me much of a sense of what you were getting at, and if I tried to guess, I'd probably get some important aspect of it wrong.  Can you describe what sort of Motte and Baily you were expecting to see?  Which position was the Motte? Which position was the Baily?

I apologize for speculating about the motte-and-bailey usage of this framing.  It pattern matches to other things I've seen where someone tries to generalize a relationship between evidence and truth in unclear ways, and then applies it to political topics where the actual propositional truth is far removed from the debate over framing and preferences.  I have no reason to believe that your intent was anything but good.

My discomfort remains, in that you don't make it clear what types of "truth" you're talking about, nor acknowledge that different experiences do lead to different predictions of future experiences,with a lot of truths being not objective, or at least not resolvable by individual humans. 

The 6 vs 9 cartoon seems like the obvious case where the participants don't have access to the cartoonist or the person/process which created the figure on the ground.  They could acknowledge that the shared truth is only that there's a pattern visible in that shape, and that it could be interpreted as a 6 or a 9 depending on context.  They CANNOT state that there is any objective truth to "what it is". or "what it is supposed to be".  

And that generalizes - it's not clear that there exists any "objective truth" at human perception levels.  All of human experience is so far abstracted and modeled by one's brain that the underlying quantum field interactions are averaged out and imperceptible.  A lot of these sums and averages can be quite confident - the likelihood that tomorrow will contain a set of particles forming a lumpy sphere spinning in a very similar way as today's Earth is pretty close to 1.  But not exactly 1 - there's always an epsilon.  Maybe the simulation ends.  Maybe we've missed something in our model of physics. Maybe something perfectly normal but very unlikely happens (like a collision with very large very fast object coming from outside the solar system).  All vanishingly unlikely, but not actually impossible.

"Cogito ergo sum" is tautalogical, so absolutely true.  But it's not objective - it doesn't prove anything (or anyone) else.

Regarding your suspicion of whether I would apply this to a political topic:  Of course I would.  There are countless political topics I would apply this to.  

The ideas behind this post are a fundamental component of the way I think,  how could it possibly not apply to many political opinions I hold?

Regarding your point about the 6 vs 9 cartoon, that's essentially the main point of this article.  When there is an objective truth about the physical world, that truth exists outside the mind, and it is distinct from our internal model of truth that's inside the mind.  

Our belief is just a simulacrum of the truth, and even though we try to make it as accurate a simulacrum as we can, it's still just a simulacrum.

And perhaps the most important point of my post, is that even though our belief is just a simulacrum of the truth, It will seem, to us, to just be the truth itself because belief is how we experience truth. 

I think that the person who wrote the black text, knows best what that symbol is supposed to be. That person is presumably the original author of the comic, and the person who created the symbol in the first place. I can’t think of a way any other person can possibly know better what the symbol is supposed to be.

Within the context of the scenario in the comic, the comic author doesn't exist, and some person wrote the symbol on the ground. In pretty much any realistic scenario, that person intended a specific reading of the symbol.

that symbol on the ground is a metaphor for more complex problems that have multiple faces.  The "realistic scenario" isn't a literal number painted on the ground.  It's more like the Ronald Cotton case mentioned further above, where there was eye witness testimony and physical evidence which pointed toward him committing the crime, but there was also DNA evidence which showed that he didn't.