An Objective Standard for Sanity

I’ve always been fascinated by so-called “crazy” people. That guy who’s convinced he’s Napoleon reincarnate because his dog told him so; the serial killer who is literally obsessed with killing people; the guy who shouts on the sidewalk every Sunday about how Jesus is actually the devil – I just can’t help but listen and observe.

Why do they believe what they believe? Are they delusional? Insane? What does “insane” even mean – is their mind somehow broken?

Or, perhaps they are the sane ones, and I’m the insane one. I don’t think they make compelling arguments, but perhaps that’s because my mind is broken, not theirs. Is there any way I can prove otherwise?

After worrying about these questions for years, I have finally settled on a conclusion. As far as I can tell, there is only one objective standard for insanity: rejecting the laws of logic. All other standards are merely social conventions.

I don’t say this because I’m partial towards logical reasoning. I mean – quite literally – if somebody denies the laws of identity and non-contradiction, their minds can be considered broken.

Method, not Conclusions

To illustrate, take a stereotypical example of a “crazy person” – somebody who’s convinced he’s Napoleon because his dog told him so. Let’s call him “Joe”. We note a few things about Joe:

A.) He holds a belief that virtually everybody in society considers false.

B.) He believes it because of a dubious methodology (his dog told him so).

Is this enough information to determine whether or not Joe’s mind is broken? Certainly not. Just because somebody believes something that nobody else believes doesn’t mean they are crazy – nor does it mean their beliefs are wrong.

Plus, the majority of people arrive at their beliefs through a dubious methodology, whether it’s blind faith or simply poor reasoning. That doesn’t mean they are all insane. We need more information.

Imagine that Joe sincerely didn’t know that “believing what your dog tells you” is a bad methodology for critical reasoning. You explain why; he sees your point of view and changes his mind.

If anything, Joe has demonstrated he’s a rational person – he changed his mind because of a better argument!

Now instead, imagine you explained the errors in his reasoning, but he wasn’t persuaded. He told you, “The reason dog’s are trustworthy is because of the arrangement of the stars; when they are aligned, then you can trust animals.”

While this is a crummy counter-argument, it’s still not enough to say Joe is insane. He could just be deeply confused about the nature of the world. You might say Joe is “ignorant” or “close-minded” – but that’s also true of the majority of people.

How many people have tried to persuade stubborn ol’ grandpa that his beliefs are false? If he doesn’t budge, it seems peculiar to conclude that he’s crazy. However, if we add one more detail, we might push Joe closer to insanity. Let’s say that:

C.) No amount of reasoned discourse will change his mind.

Instead of putting forward poor arguments about the alignment of the stars, imagine Joe rejects the very principle of persuasion. There’s literally no argument which could ever change his mind.

In my mind, this gets closer to the edge of sanity – it puts him beyond the reaches of Reason and rationality.

However, it’s at least conceivable that one can be sane and yet not persuaded by rational discourse. Consider a Buddhist who is convinced that the truth must be experienced, not communicated. Language, to the Buddhist, is usually a distraction. Therefore, a monk might reasonably reject the principle of persuasion altogether. Does that make him crazy? Probably not.

It’s About Logic

Contrast these examples with an explicit denial of logic. Imagine a female friend comes up to you and says, “I am pregnant!”

Naturally, you celebrate with her. Then she says, “I am not pregnant!”

What do you think? Maybe she just pranked you. You ask her:

“Wait a second – are you pregnant or not pregnant?”

She responds, “I am pregnant and not pregnant!”

You can tell she isn’t joking; she’s serious. So you have a dialogue:

“Hang on. You can’t be both pregnant and not pregnant. It’s one or the other. Let’s start over: are you absolutely sure that a) it is true that you are pregnant.”


“Then it must be true that b) you aren’t not-pregnant. If you were actually not-pregnant, then you wouldn’t be pregnant in the first place!”

“I am both. It’s true that I am, and it is equally true that I am not. It is true and false at the same time.”

What would you conclude? You might start seriously thinking that your friend is nuts – her mind might be broken. But you decide to try one more time:

“It’s not possible for something to be true and false at the same time. If it’s true that you’re pregnant, then you must actually be pregnant – you can’t be not-pregnant and pregnant! What we mean by ‘not-pregnant’ is precisely the opposite of being pregnant!”

“My friend, you are just using logic. I embrace the logical contradiction. I am large; I contain multitudes.

Alas, as far as I can tell, this person is objectively insane. It’s not because of her conclusions, per se; anybody can accidentally have a contradictory belief. It’s because of her rejection of logic – the ultimate methodological mistake.

By rejecting logic, she’s not only beyond the reach of Reason. She’s beyond coherence. Not only will she never be persuaded by another argument – her own arguments aren’t even internally consistent. They are explicitly irrational; they cannot make sense.

While the Buddhist, by contrast, might believe that “the truth is more accurately understood in silent meditation,” the insane person thinks, “There is no such thing as truth” – an explicit self-contradiction.

The Buddhist might think, “Reason and logic will never reveal the experiential truth about the world.” The insane person thinks, “Reason and logic are self-contradictory and so is the world.”

Logic underpins every belief, every methodology, and every thought. It is necessary and inescapable. Logic is necessary for comprehension of any sort, and it is what all arguments ultimately appeal to. Therefore:

Rejecting the rules of logic is identical with rejecting sanity.

Of course, by “rejecting the rules of logic”, I mean denying the self-evident truth that “things are the way they are.” If somebody cannot accept this, then their mind is not working correctly. They are insane.

Because human actions follow directly from our beliefs about the world, you cannot predict how insane people will act. There’s no sensibility – no consistency – to their beliefs, so there’s nothing holding them back from completely impulsive or erratic behavior.

Don’t get me wrong: I’m not saying everybody who is insane is erratic. But I am saying  the potential is there; they aren’t ultimately grounded. There’s no beliefs holding them back from acting in accordance with an endless string of non-sequiturs.

One Metric

Thus, we have an answer to disturbing questions about our own sanity. How can we ever know if we’re crazy? Don’t crazy people think they are sane – precisely because they are crazy?

The answer is clear: think about the laws of logic. If you accept that “A is A”, then you must have some measure of sanity. Granted, being sane doesn’t mean your conclusions about the world are right – but it does mean your mind isn’t fundamentally broken.

Plus, acknowledging the laws of logic gives you common ground with other sane people. Regardless of how different two people’s worldviews are, they can always point to the inescapable laws of logic as something they agree on.

Contrary to popular opinion, sanity is not determined by social convention. Even if all-but-one person rejected logical rules – that one person would be completely justified in calling everyone else insane. Granted, that one person might not be popular, but at least he would be right.