Published on November 6, 2025 4:03 AM GMT

WARNING: This post contains spoilers for Harry Potter and the Methods of Rationality, and I will not warn about them further. Also some anecdotes from slutcon which are not particularly NSFW, but it’s still slutcon.

A girl I was seeing once asked me to guess what Hogwarts house she was trying to channel with her outfit. Her answer turned out to be Slytherin, because the tiny gem in the necklace she was wearing was green. Never mind that nothing else she wore was green, including the gems in her earrings, and that colors of all the other Hogwarts houses appeared in her outfit (several more prominently), and that the gem itself was barely visible enough to tell the color at all, and that she wasn’t doing anything to draw attention to the necklace specifically.^[1]

I wonder, sometimes, just how much of the “subtle social signals” people think they’re sending are like that case - i.e. it’s basically a game with themselves, which has utterly zero signal for anyone else.

Subtlety to the point of invisibility clearly happens more than zero percent of the time; I have seen at least that one unambiguous case, so existence is at least established. But just what should our priors be on any given subtle signal being received, in various domains?

Just How Subtle Is The Signal?

Hints in Writing

A little blurb from Eliezer on his domain of unique expertise:

So the big thing to remember about all of HPMOR is that, just as in the original books, the Defence Professor was Voldemort, and I thought it would be way way more obvious than it was to the readers.

[…]

The number one thing HPMOR taught me as an author is that you are being so much less clear than you think you are being. You are telegraphing so much less than you think. All of the obvious reads are so much less obvious than you think. And if you try to have subtle hints and foreshadowing laced through the story, clues that will only make sense in retrospect, that’s way too subtle.

Instead, you should just write very plainly reflecting the secrets of the story. Don’t try to hide them, but don’t explicitly spell them out either. That will be just right.

Fun subquestion for those who’ve read HPMOR: on the first readthrough, did you correctly guess what “might be big and grey and shaped like a cauldron”?

I use this mainly as a prior for thinking about more common subtle social signals.

Hints in Flirting

For subtle hints involved in flirting, there’s an obvious test: take the usual classroom full of undergrad psych students, pair them up, have them do some stuff, then ask them afterward (a) whether they were flirting with their partner, and (b) whether their partner was flirting with them. Of course this has been done before, producing a paper with far too small a sample size to be taken very seriously, but it at least gives a qualitative baseline. Results:

Key fact which is not in the table: most people are not flirting most of the time, so naturally people usually guess that they are not being flirted with; thus the high accuracy rates when one’s partner is not flirting.

The interesting part is how often peoples’ flirting was picked up upon when people did flirt. And, uh… the numbers are not real high. When males flirted, it was picked up 36% of the time. When females flirted, it was picked up 18% of the time. And while I do not think one should take these numbers very seriously, I will note that female flirting was also detected 17% of the time when the female did not flirt, so at least according to these numbers… female flirting gave basically zero signal above baseline noise.

Males flirting at least managed to send some signal above baseline noise, but in most cases their signals still were not received.

So insofar as we expect this one too-small study to generalize… it sure seems like most flirting, and especially most female flirting, is somebody playing a game with themselves which will not be noticed.

Hints in Outfit

We covered one example at the beginning. More generally… it seems like there’s something weird going on in a lot of peoples’ heads when it comes to their clothes.

At least among people who put in any effort to their wardrobe, you’d think the obvious question influencing clothing choice would be “what vibe do other people get from this?”. Personally, thanks to slutcon a few weeks ago, I now have a fair bit of data on what vibe people get from my wardrobe choices (and bearing more generally), at least for sexual purposes. The consensus feedback said roughly “creepy/rapey, but in the sexy way”, which matches what I’m going for pretty well (think Rhysand, or any other romance novel guy matching that very popular trope^[2]). Not perfectly, and the mismatches were useful to hear, but I’m basically on target. And it’s a very popular target, apparently.

I don’t know what is going on in other peoples’ heads, when it comes to their wardrobes. Most people look generic, which makes sense if you’re not putting much thought into it… but most people I know who do put thought into it also look generic! There are exceptions, and they are notable. But the typical case seems like the opening example: someone will try to channel House Slytherin by wearing a tiny green gem in an outfit which otherwise doesn’t have anything to do with Slytherin.

Oblivious?

Of course one reaction to all this is “John, maybe people do pick up on things and you’re just particularly oblivious”. And that’s reasonable on priors, it’s what I thought for a long time too. But man, the evidence just keeps pointing in the other direction. I personally have repeatedly received feedback (e.g. in circling) that I’m unusually good at reading people. When I go look for data (like e.g. the flirting study above), it agrees. When I look for particularly unambiguous examples (like e.g. the green gem signalling Slytherin), I find them.

… anyway, the weird thing is what happens when I point this sort of thing out.

Emotional Investment?

It feels like people are really attached, for some reason, to pretending that their subtle signals are actually useful somehow.

Point out that women attempting to flirt seem to almost universally fail to send any signal at all, even to other women (the paper above did check that), and someone will say something like “well, mind-reading seems like a good thing to select for, for dating purposes”. Point out that most peoples’ clothes don’t really manage to signal what they intended even when they’re trying, and someone will say something like “well, it’s largely about signalling to oneself, e.g. to build confidence, so it doesn’t matter if other people get the signal”. And, like… I roll to disbelieve?

I opened with that example of the girl trying to signal Slytherin with the gem. I could see her reaction when I did not immediately guess which house she was going for, and quickly tried to navigate out of the situation. She was not expecting that nobody else could pick up on the signal.

Another slutcon example: some time after one encounter, I learned that a girl was trying to strongly signal “yes” to me with her body, without saying anything. And she did that by… looking like she was about to fall asleep. Just kind of out of it. This girl was not trying to select for mind reading, she intended to send a signal, she was just utterly miscalibrated.

C’mon, guys. People are not playing these games for some clever reason which makes sense in the absence of other people picking up the signals. Yet at the same time, people seem really emotionally invested in their so-called signals. Somehow, this seems to trigger its own flavor of rationalization or something. My best current articulation is: a person builds their whole identity in their heads, and imagines that other people see them that way, and is happy whenever somebody makes them “feel seen” by picking up on that identity (… albeit probably sometimes accidentally), and is disappointed when people don’t pick up on it. And so it would be a pretty massive disappointment if some huge chunk of the identity-signals the person thought they were sending just… weren’t actually received. So they grab for some story which somehow keeps their identity intact.

My response to that is: think how great it would feel if you were just… seen by the vast majority of people around you, all the time. In order for that to happen, you need to first accept that you’re not already seen most of the time, and it’s a thing you can change via your own actions (as opposed to wishing that other people become better mind-readers), so maybe do that. Send some actual signals.

1. I did not critique the dubious signal-to-noise ratio to her at the time.

2. I am lucky in that my tastes match a popular romance novel trope well, so leaning into it feels intuitive and genuine and like letting out my real self.