AI doesn't need to understand to answer

AI 不必真的懂,也能生成答案
TL;DR
  • AI answering well doesn’t mean it really understands. It uses the Transformer’s attention mechanism to find relationships and fill in structure within the context and generate the most reasonable expression, without needing to understand first and then answer the way people do.
  • So AI is very good at following context, but context isn’t reality. If the premise is wrong or information is missing, it will follow the error along, and do so very naturally.
  • Rather than asking it to “just tell me the answer,” give it enough context and ask it to lay out the possibilities, point out blind spots, and tell me which parts need checking against facts and sources.

The last post said that AI’s answers don’t come out of a “database of truth”; they’re the most likely response generated within the current context.

But that raises another question:

if AI doesn’t really “know the answer,” why does it so often answer so well?

You say something very vague and it fills in what you mean. You paste a messy passage and it pulls out a structure. You ask for a different tone and it rewrites right away. You say “not so AI-sounding,” and it even understands what exactly you dislike.

That easily gives people the feeling:

it seems to really understand.

But a more accurate way to put it may be:

AI can generate answers it doesn’t need to truly understand.

That isn’t to say AI lacks ability. It’s that the source of its ability is different from the way humans understand.

We assume: answers come from understanding

For people, it’s usually understand first, then answer.

For example, if I ask you:

is this email too harsh?

you understand the tone, the relationship, the situation and the consequences, then judge how it should change.

So we naturally assume:

can answer = understands.

But AI doesn’t work entirely like that.

It doesn’t need to have lived through the thing like a person, or bear the real consequences like a person, to generate an answer that looks complete, fluent, even useful.

That’s what’s most magical about AI, and what most easily leads people to misjudge it.

How can it do that?

There’s an important technical term here:

Transformer.

First, the big picture: the Transformer isn’t “the one foundation of all AI.”

AI has many other approaches: recommender systems, traditional machine learning, diffusion models, reinforcement learning, robot control and more.

But if we’re talking about today’s mainstream chat-style AI / large language models, the Transformer is one of the most important architectural foundations.

In 2017 there was a paper that later became very important, titled:

Attention Is All You Need.

Note that it isn’t an inspirational quote. It’s the title of a paper.

The paper introduced the Transformer architecture and made attention a concept you can’t avoid when trying to understand modern large language models.

Attention isn’t “attention” in the psychological sense

Many people seeing “attention” for the first time assume it means a person’s attention in the psychological sense.

But here, attention is more precisely a mechanism that lets the model compute how strongly different tokens in the context relate to each other.

In plain words:

which information in the context should the current word draw on? And how much?

A simple example:

The animal didn’t cross the street because it was tired.

Who does “it” refer to here?

A person knows at a glance it’s the animal, not the street. But the model has to judge:

which earlier word should this “it” be more strongly related to?

That’s one kind of problem attention is meant to solve.

It doesn’t look at every word equally. It judges which information matters more and should be drawn on more.

So AI is very good at handling context

That’s also why AI can do many things that look like “understanding”:

It can summarize an article because it can catch what matters in the context. It can change tone because it can recognize style. It can pick up from what came before because it can track relationships in the context. It can help you sort out messy thoughts because it can reorganize the structure in language.

That’s why the prompt matters.

The clearer the context you give it, the easier it is for it to generate a useful answer. The messier the information you give it, the more likely it is to keep generating along a wrong premise.

A lot of the time, it isn’t that AI “suddenly got dumb.” It’s that, within an incomplete, inaccurate or biased context, it generated an answer that looks complete.

But context isn’t reality

Here’s the key boundary:

AI is very good at handling relationships within language. But relationships within language aren’t the truth of reality.

It can tell who “it” refers to in a sentence. But it doesn’t necessarily know whether a policy is still in effect.

It can help you analyze the possible reasons someone replied coldly. But it can’t really know what they’re thinking.

It can help you write a very polite email. But it won’t bear the consequences of that email once it’s sent.

So AI’s strength isn’t that it has experienced the world like a person. It’s that it’s extremely good at finding relationships, filling in structure and generating reasonable expression within language and context.

That explains why it’s sometimes extremely useful. And why it’s sometimes wrong in a very natural way.

Because what it picks up is the context, not reality itself.

How should ordinary people use it?

Understanding the Transformer isn’t about turning yourself into an engineer.

Ordinary people only need to remember three things:

First, AI is very good at following context, so the clearer the information you give it, the better its answer usually is.

Second, AI generates answers along the context, so if your premise is wrong, information is missing or emotion has skewed things, it may follow the error along.

Third, AI generating a good answer doesn’t mean it really knows what happened in reality.

So the better way to ask isn’t:

just tell me the answer.

It’s:

I’ll give you enough context; please help me lay out the possibilities, point out blind spots, and tell me which parts need verifying.

In a sentence:

AI doesn’t need to understand like a person to generate a useful answer. But whether it’s actually right still comes back to facts, sources and checking against reality.

This is part 2 of the series “how ordinary people can trust AI the right way.” Next I want to talk about which questions suit AI, and which can’t be handed over to it entirely.

Written in Chinese and translated into English with the help of AI. Read the original