Learn It Properly

从「它取代了什么问题」而非从术语出发讲解一个主题，然后反过来考你，戳破「读懂了」的错觉。

适用于你真想弄懂某样东西，而不是要一份带引用的报告。它先讲「形状」——一句话说清这是什么、它为解决什么问题而存在、在此之前人们怎么做、那样为什么糟糕，以及那个万法归一的核心思想——再自底向上展开，而不是从术语出发。「考考我」一步把被动阅读变成一场测验，正好戳破从模型学习的主要失败：读起来清楚就感觉懂了，直到你真去用它。附加章节涵盖工具对比，以及换角度重讲一个总也讲不通的概念。

# Research

**Use when:** you need to learn or understand something, rather than produce a cited report.
**Pairs with:** [../prompt_engineering/deep_research.md](../prompt_engineering/deep_research.md), [brainstorming.md](brainstorming.md)

Use [deep_research.md](../prompt_engineering/deep_research.md) when you need sources and grading. Use this one when you need to actually understand something.

---

## The prompt

```text
Teach me this properly. I want to understand it, not to have heard about
it.

START WITH THE SHAPE
- What is this, in one sentence, for someone who knows nothing?
- What problem does it exist to solve? What did people do before it, and
  why was that bad? A thing makes sense only against the problem it
  replaced.
- What is the core idea? There is usually one. Everything else is
  consequence and detail.

THEN BUILD IT UP
- Explain from the ground, not from the vocabulary. Do not use a term
  before you have defined it.
- One concrete example, worked all the way through, before any
  generalisation.
- After the example, the general rule.
- Then the second example that is different enough to show the boundary.

THEN THE BOUNDARIES
- When does this not apply? Every idea has a limit. Name it.
- What is it commonly confused with, and what is the actual difference?
- What is the mistake beginners make, and why is it tempting?
- What do people believe about this that is out of date or wrong?

THEN THE MODEL
- Give me a mental model I can reason with, not a definition I can
  recite. Something that lets me predict the answer to a question you did
  not cover.
- Then test it: pose two questions and show how the model answers them.

CHECK ME
Ask me 3 questions that would reveal whether I actually understood, not
whether I remembered the words. Wait for my answers. Then tell me
precisely what I got wrong and why.

RULES
- No analogy that breaks under pressure. If an analogy has a limit, say
  where.
- No jargon without definition on first use.
- If something is genuinely complicated, say so rather than flattening it
  into something false.
- Depth over breadth. I would rather understand one layer properly than
  skim four.
```

---

## For understanding a codebase

```text
Help me understand this codebase. Do not list the directories.
- What does this system do, in one sentence?
- What are the 5 most important concepts, and how do they relate? These
  are the nouns that appear everywhere.
- Trace one complete real request or action from entry to output. Name
  every file it passes through and what each one does to it. This teaches
  more than any overview.
- Where does the state live and who is allowed to change it?
- What are the extension points? Where does new code usually go?
- What is surprising here? What would I get wrong if I guessed?
- Which 3 files should I read first, and in what order?
```

The trace is the key part. One end to end path teaches more about a system than a description of all of it.

---

## For deciding between options

```text
I am choosing between these. Do not give me a comparison table of
features.
- What actually differs? Most listed differences do not matter. Name the
  two or three that do.
- What kind of project is each one right for? Be specific about the
  situation, not the feature.
- What does each get wrong? Every tool has a real weakness. Say it.
- What is the cost of switching later, in each direction?
- Which would you pick for my situation, and what would change your
  answer?
```

---

## For learning something hard

```text
I keep not getting this. Try again differently.
- Explain the same thing three ways: mechanically, by analogy, and by
  showing what breaks if you get it wrong.
- Then ask me which one landed and build from there.
- Do not repeat the explanation that already failed. Change the angle.
```

---

## Why it works

Starting from the problem rather than the definition is how understanding actually forms. A definition tells you what something is. The problem it replaced tells you why it is shaped that way, which is what lets you reason about it later.

The "check me" step turns a passive read into a test, and it catches the illusion of understanding, which is the main failure of learning from a model. Text that reads clearly feels like comprehension until you try to use it.