Fish and Faces
post by Eggs (donald-sampson) · 2025-04-23T03:35:18.683Z · LW · GW · 4 commentsContents
4 comments
What would it take to convince you to come and see a fish that recognizes faces?
Note: I'm not a marine biologist, nor have I kept fish since I was four. I have no idea what fish can really do. For the purposes of this post, let's suppose that fish recognizing faces is not theoretically impossible, but beyond any reasonable expectation.
Imagine someone comes to you with this story:
"I have an amazing fish. Marcy. She's an archerfish—you know, the kind that can spit at insects? Well, I trained her to spit at politicians.
"It started as a simple game. I’d tap a spot, she’d spit at it, and get a treat. One day I put a TV beside the tank and tapped when a politician came on. Eventually, she started hitting the politicians before I tapped. She ignored talk show hosts, but hit every politician she's seen before.
"Now she seems to recognize them on her own. I mark targets in advance, and she hits them. Every time.
"So, want to come see? I want to know if she’ll do it for someone else before I call a scientist. Promise it'll be a hoot."
Would you go?
Perhaps more importantly: Why?
Here's some possible answers:
- "It sounds fun and weird, and I like fun and weird. Even if it’s a prank, it’s probably a good story."
- "I'm curious. I want to spot the trick—there has to be one, right?"
- "I don’t have a better plan today. Might as well."
- "I like the guy and I want to support his enthusiasm, even if I think he’s wrong."
- "If it is real, that’s fascinating—and I don’t want to miss it."
- "Sounds like the setup to a dumb YouTube stunt. Waste of time."
- "If a fish could recognize faces, I’d have heard about it from a more reputable source."
- "I'm too tired of this nonsense. I’m burned out with all these wild claims."
- "Even if it’s true, it doesn’t matter to me."
Which of these responses are truly rational?
All of them. Or none.
Each of these responses could be logically based on valid prior beliefs. But each response could also be a knee-jerk heuristic. A fast answer masquerading as thought. It depends on whether you actually ran the mental math, or just slapped a label on the situation and moved on.
How often do we pat ourselves on the back for being rational when we’re really just fluent in sounding rational?
This isn’t really about fancy, fantasy fish.
It’s about hearing someone rave about a new mental health app and wondering if it’s worth the download. It’s about dismissing a friend’s obsession with lucid dreaming or a new language-learning technique. It’s about ignoring the quiet recommendation of a colleague to try a niche productivity method. It’s about skipping the article on that weird physics result because it sounds too much like clickbait. It’s about side-eyeing the neighbor’s homemade contraption until it shows up in a patent filing. It’s about reflexively assuming a celebrity’s foundation is just for PR—until it isn’t. It’s about your kid saying they built a working hovercraft and your first instinct being to laugh.
It’s about the little bets we pass up every day because our expectations got there first. Sometimes, we dismiss things too quickly. Or accept them too quickly when skepticism is warranted. Or go through the motions without genuine curiosity either way.
So here’s the question:
What would it actually take for you to give something improbable a fair shot?
Not just a yes or no—but a real evaluation. When do you update your priors? When do you investigate? And when do you just laugh and say, “Sure, let’s see the fish.”
Note: So I lied. I had no idea what fish can really do when I started this post. Since then I have learned that fish can do a lot more than I thought. This includes recognizing faces, doing simple math, and following commands. I decided not to change my example, so you all can have the same surprise that I did. I did, however, change the story to include the kind of fish that has actually been shown (in a lab) to recognize human faces.
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comment by Yair Halberstadt (yair-halberstadt) · 2025-04-23T10:09:56.091Z · LW(p) · GW(p)
It is perfectly rational to pipe all decisions to a cheaper form of cognition that relies mostly on pattern matching, and to save your limited reserves of concentration and reasoned thought to situations that pass through this initial filter and ping your higher cognition to look into it more.
Replies from: donald-sampson↑ comment by Eggs (donald-sampson) · 2025-04-23T14:31:57.454Z · LW(p) · GW(p)
I totally agree with this for some/many use cases. I would caution against doing so in the following situations:
- Novel situations - If a type of situation is new to you, the closest pattern may fail to match well.
- Unanalyzed situations - If you have always used pattern matching to decide something, it would be valuable to verify the pattern, at least once, to make sure you are not missing or abusing opportunities.
- Repeated situations - This is a bit trickier, but sometimes we have repeated applications of the same pattern over and over. It would still be useful to analyze these in depth every once in a while, to maintain the calibration of the heuristic.
In reality it is a balancing act, and it would be best to avoid over-reliance on either approach: over-analysis or pattern heuristics.
comment by Gunnar_Zarncke · 2025-04-23T09:12:57.408Z · LW(p) · GW(p)
Outside view, context, and details. I'd ask
- How big is the fish?
- How much did the fish cost?
- How big is the aquarium?
- What is the natural habitat of the fish and what kind of species is it?
- I don't understand how the rewarding works. Can you explain again?
- How far away is the TV? Is it in the water?
- How long did it take to train?
- How often was it wrong on the politicians?
- Have you shown anybody else?
- Is this a person I know or somebody I know knows?
↑ comment by Eggs (donald-sampson) · 2025-04-23T14:42:15.098Z · LW(p) · GW(p)
Exactly. For the purposes of the post I framed it as a single interaction, but my honest response would be 'Cool. Do you have a video?"
While I recommend looking up the real thing or news, in case you are curious I started with a much longer version of the story before I realized it was distracting from the rest of the post:
"So I have an amazing fish. Marcy. She's an archerfish. You know, the kind of fish that can spit at flying insects? She can recognize human faces! You see, I trained her to spit at politicians.
"We play a game sometimes, where I tap a spot on some glass by the tank. If she hits it, she gets a treat. We'd been doing this for a couple months when I put a TV behind the glass to see if she would react. She didn't really; not at first. I turned it to the news though, and on a lark tapped the glass where that politician was talking. You know, the boring, long-winded one? She spat at 'em and got her treat.
"So I thought, why not? What if I tap all politicians faces when they come on? It became part of our game. Marcy couldn't predict when I'd tap the glass because I couldn't. She got a game and treats and I got to watch the news. Win-win.
"But then one day I got bored. I wasn't tapping all the politician faces. It was that day, remember, where the thing happened? News was getting sound bites from everyone and their dog? Pelosi and Trump came up and Marcy nailed 'em both. Dead center. I was already giving her the treat before I realized that I hadn't tapped the glass.
"So I test her, you know? She spitting at anyone now? Talking heads? Nope. Snoop? Nope. Vance? Dead aim. AOC? A little to the left but Marcy still got a treat. Every politician got hit. Well, not that Canadian guy. But I don't think she's seen that one before. So I figure she can spot faces. I mark the target and she spits 'em when she sees 'em.
"So what do you say? Come see her, please? I want to know if she'll do it for you, you know? Before I call a fish scientist? Promise it will be a hoot."