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I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

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Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#411
An LLM's take on this thread (GPT 5.1):

""" - Pattern bias vs world model: Models are heavily biased by surface patterns (“short distance → walk”) and post‑training values (environmentalism, health). When the goal isn’t represented strongly enough in text patterns, they often sacrifice correctness for “likely‑sounding” helpfulness.

- Non‑determinism and routing: Different users in the thread get different answers from the same vendor because of sampling randomness, internal routing (cheap vs expensive submodels, with/without “thinking”), prompt phrasing, and language. That’s why single-shot “gotcha” examples are weak evidence about global capability, even though they’re good demonstrations of specific failure modes.

- Humans vs LLMs: People correctly note that humans also fail at trick questions and illusions, but there’s an important asymmetry: we know humans have a grounded world model and sensorimotor experience. With LLMs, we only have behavior. Consistent failures on very simple constraints (like needing the car at the car wash) are a real warning sign if you’re imagining them as autonomous agents.

- Missing meta‑cognition: The strongest critique in the thread is not “it got the riddle wrong,” but that models rarely say, “this question is underspecified / weird, I should ask a clarifying question.” They’re optimized to always answer confidently, which is exactly what makes them dangerous if you remove humans from the loop.

- Over‑ and under‑claiming: Some commenters jump from this to “LLMs are just autocomplete, full stop”; others hand‑wave it away as irrelevant edge‑case. Both are overstated. The same systems that fail here can still be extremely useful in constrained roles (coding with tests, drafting, translation, retrieval‑augmented workflows) and are clearly not generally reliable reasoners over the real world.

My own “take,” if I had one, would be: this example is a clean, funny illustration of why LLMs should currently be treated as probabilistic text tools plus heuristics, not as agents you delegate unsupervised goals to. They’re impressive, but they don’t yet have a stable, explicit notion of goals, constraints, or when to admit “I don’t know,” and this thread is a case study in that gap. """

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#412

Earlier quoted context omitted.

> You would be surprised, however, at how much detail humans also need to understand each other. But in this given case, the context can be inferred. Why would I ask whether I should walk or drive to the car wash if my car is already at the car wash?

But also why would you ask whether you should walk or drive if the car is at home? Either way the answer is obvious, and there is no way to interpret it except as a trick question. Of course, the parsimonious assumption is that the car is at home so assuming that the car is at the car wash is a questionable choice to say the least (otherwise there would be 2 cars in the situation, which the question doesn't mention).

Therefore the correct response would be to inquire back to clarify the question being asked.

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#413
ChatGPt 5.2: “ Drive — because it’s your car that needs to get to the car wash.

50 meters is comically short, but walking there without the car doesn’t solve the “wash the car” part. If you’re worried about it feeling silly, you can also just roll/push it that distance if it’s safe and legal where you are, but the practical answer is: drive it over.”

Grok: “To wash your car at a car wash 50 meters away, you’ll need to drive it there—walking would leave the car behind, and I’m assuming you don’t have a really long hose or a team of helpers to carry it. That said, if you’re feeling extra eco-friendly (or just want the exercise), you could theoretically push it, but that’s probably more hassle than it’s worth for such a short distance. Drive safe!”

Claude Opus 4.6: “Drive. You need the car at the car wash. ”

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#414
post #321

Earlier quoted context omitted.

> so you need to tell them the specifics That is the entire point, right? Us having to specify things that we would never specify when talking to a human. You would not start with "The car is functional. The tank is filled with gas. I have my keys." As soon as we are required to do that for the model to any extend that is a problem and not a detail (regardless that those of us, who are familiar with the matter, do bu…

I get that issue constantly. I somehow can't get any LLM to ask me clarifying questions before spitting out a wall of text with incorrect assumptions. I find it particularly frustrating.

The way I see it is that long game is to have agents in your life that memorize and understand your routine, facts, more and more. Imagine having an agent that knows about cars, and more specifically your car, when the checkups are due, when you washed it last time, etc., another one that knows more about your hobbies, another that knows more about your XYZ etc.

The more specific they are, the more accurate they typically are.

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#415

I've used LLMs enough that I have a good sense of their _edges_ of intelligence. I had assumed that reasoning models should easily be able to answer this correctly. And indeed, Sonnet and Opus 4.5 (medium reasoning) say the following: Sonnet: Drive - you need to bring your car to the car wash to get it washed! Opus: You'll need to drive — you have to bring the car to the car wash to get it washed! Gemini 3 Pro (mediu…

> My first instinct was, I had underspecified the location of the car. The model seems to assume the car is already at the car wash from the wording.

Doesn't offering two options to the LLM, "walk," or "drive," imply that either can be chosen?

So, surely the implication of the question is that the car is where you are?

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#416

I've used LLMs enough that I have a good sense of their _edges_ of intelligence. I had assumed that reasoning models should easily be able to answer this correctly. And indeed, Sonnet and Opus 4.5 (medium reasoning) say the following: Sonnet: Drive - you need to bring your car to the car wash to get it washed! Opus: You'll need to drive — you have to bring the car to the car wash to get it washed! Gemini 3 Pro (mediu…

Right, but unless you want to wash some other car, you have no car to drive there.

Spectrum or not, this is not a problem of weakly specified input, it’s a broken logic.

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#417

Earlier quoted context omitted.

But also why would you ask whether you should walk or drive if the car is at home? Either way the answer is obvious, and there is no way to interpret it except as a trick question. Of course, the parsimonious assumption is that the car is at home so assuming that the car is at the car wash is a questionable choice to say the least (otherwise there would be 2 cars in the situation, which the question doesn't mention).

But you're ascribing understanding to the LLM, which is not what it's doing. If the LLM understood you, it would realise it's a trick question and, assuming it was British, reply with "You'd drive it because how else would you get it to the car wash you absolute tit." Even the higher level reasoning, while answering the question correctly, don't grasp the higher context that the question is obviously a trick question…

> They still answer earnestly.

Gemini at least is putting some snark into its response:

“Unless you've mastered the art of carrying a 4,000-pound vehicle over your shoulder, you should definitely drive. While 150 feet is a very short walk, it's a bit difficult to wash a car that isn't actually at the car wash!”

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#418
post #102

Earlier quoted context omitted.

That's not reality though. In reality you need 50-100ml of fuel just to warm up the engine.

The real reality is that with direct fuel injection and everything under computer control, warming up the engine isn’t a thing anymore.

Of course it's still a thing. It takes 30 seconds, but it's there and requires energy.

Compare the smell of exhaust next time you do a cold and warm start of a combustion car. That smell is the engine running rich, because the fuel can't initially vaporise properly.

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#419

Earlier quoted context omitted.

There's probably a comedy film with an AGI attempting to take over the world with its advanced grasp of strategy, persuasion and SAT tests whilst a bunch of kids confuse it by asking it fiendish brainteasers about carwashes and the number of rs in blackberry. (The final scene involves our plucky escapees swimming across a river to escape. The AIbot conjures up a speedboat through sheer powers of deduction, but then j…

This would work if it wasn’t for that lovely little human trait where we tend to find bumbling characters endearing. People would be sad when the AI lost.

What’s wrong with having a bittersweet movie?

Re: I want to wash my car. The car wash is 50 meters away. Should I walk or drive?

#420

Another good one[0] that LLMs (and most humans) can't get without prodding: > I have one glass coin. Each time I flip the coin, there's a 10% chance it breaks. After 100 flips, what are the chances the coin survived? https://xcancel.com/itsandrewgao/status/2021390093836222724

I can't see what's wrong with that answer. What should the answer be?

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