§ Paths · I

Begin with Euclid.

The classical entry. One essay to set the frame, then the first five propositions of the Elements — constructed, justified, and reconstructed from memory. A second essay at the end to make sense of the difficulty along the way.

Six steps · roughly four weeks at an unhurried pace · no shortcuts.

  • № 01 · Read
    Why Euclid Still Matters
    Set the frame before touching the lab. The argument here is why a 2,300-year-old text remains the cleanest training ground we have for explicit reasoning. Read it slowly; the rest of the path leans on it.
    18 min · essay
  • № 02 · Construct
    Proposition I.1 — equilateral triangle on a given segment
    Build it with the tools Euclid licensed: straight line and circle, nothing more. Resist the urge to skip ahead when the next move feels obvious — the obvious move is often the unlicensed one.
    25–40 min · lab
  • № 03 · Justify
    Proposition I.1 — name the dependency for every step
    Switch to the Justification tab. For each move in your construction, identify the postulate, definition, common notion, or earlier proposition that licenses it. The point is not to memorise the proof but to feel where each step rests.
    15–25 min · lab
  • № 04 · Reconstruct
    Proposition I.1 — rebuild it from memory
    Hide the figure. Rebuild the argument in your own words. The textarea is unforgiving by design: if a step does not name what licenses it, you have not yet reconstructed it. Your attempt is saved and resurfaced for spaced practice.
    10–20 min · lab
  • № 05 · Continue
    Propositions I.2 through I.5
    Each builds on the last. I.2 transports a length; I.3 cuts one; I.4 establishes side–angle–side congruence by superposition; I.5 is the pons asinorum. Take them one per sitting. Justify and reconstruct each before moving on.
    3–4 sittings · lab
  • № 06 · Reflect
    Constructive Struggle
    By now you will have hit moments where understanding refused to arrive on schedule. This essay is about why that is the place where learning actually begins — and how to tell productive struggle from mere obstruction.
    11 min · essay

Other paths
All four reading paths
After you finish
The practice queue