funlean.
A reading order for this chapter

The impossible order

The prerequisites are included before the words that depend on them. Skip what you already know.

Start with step one → Return to the story

  1. Reading a Lean statement

    High school

    Separate the objects, their conditions, and the conclusion.

  2. Powers and positive integers

    Middle school

    A power repeats multiplication; positive integers start at one.

  3. Prime numbers

    Middle school

    A prime is at least two and has no positive divisors except one and itself.

  4. Even, odd, and case splits

    High school

    Splitting numbers into even and odd is the proof’s own first case distinction.

  5. A hypothetical counterexample

    High school

    Assume a forbidden solution exists, then keep its evidence together.

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The impossible order · A reading order for this chapter

One thing at a time

Start with the cake-scale story. You only need to read one small piece at a time. If you are in the Fermat story, start with Story depth, then the words listed before the chapter.

In simpler words

You do not need to know Lean, symbols or university mathematics to begin. Definitions come first in the small stories.

A small clue

Look at the small example before the general formula. Ask what changed and what stayed the same.

Close this panel to return to the exact place you were reading. These are prepared hints for this page.

Start with the first small story →