mēdes
Coming soon

mēdes · a reading room for difficult ideas · in the lab

The page holds still.
You go deeper.

Open any book you own. When a sentence stops you, pull on the word. The page opens right there, beneath the line, and shows you what’s underneath. Pull again, as deep as you need. Then surface exactly where you were.

Join the first readers The passage below works. Pull an underlined phrase.
Your book · Ch. 4 · Reading evidence depth 0 · surface

4.2 When a positive isn’t

Suppose 1 person in 100 has a certain condition. A screening test catches 90 of every 100 people who have it, and wrongly flags 5 of every 100 who don’t. Your result comes back positive. What are the chances you actually have it?
Most people say about ninety percent. The real answer is closer to fifteen. The puzzle dissolves once you take the seriously, and stop reading as though it were . The two are linked by , but they are different numbers answering different questions.
Esc closes the deepest layer · select any text to pull it Sample passage written for this preview
−1

A figure built for your blocker,
not a chart about the topic.

The confusion above isn’t “probability.” It’s one specific thing: which crowd sits under the fraction. So Medes builds a living figure around exactly that. It shows one case three ways and keeps them in sync. Pick a crowd and watch it move.

Illustrative · not from your book

Which crowd are we counting inside?

Gather

    Try this · optional, never graded

    For P(condition | positive), which crowd goes on the bottom of the fraction?

    −2

    Some questions hide an assumption.
    Medes hands it to you.

    “What happens to kinetic energy if you double the mass?” The honest answer is: it depends on what you keep still. Choose what to keep fixed, then change the mass.

    Illustrative · instrument: vary one thing

    −3

    Not every blocker is a formula.

    In history, law, literature and research, the trouble is often a sentence quoted without its neighbours. Medes widens the frame around it, then asks you a question it will never grade.

    Read in context · runs on your device · no model call

    The fire at Hallow is attested in the diary of Marta Venn, the ferry-keeper, whose entry for the fifteenth describes “the bridge alight from end to end” and soldiers on the far bank.

    Two independent accounts confirm that the river bridge at Hallow was burned on the night of the fourteenth.

    The second account, the Courier’s report of the twenty-ninth, is usually cited as corroboration. Its correspondent, however, names Venn’s diary as his only source.

    Sample passage written for this preview. Hallow is fictional.

    −4

    Five promises, all the way down.

    1. The original is never rewritten.

      Your book stays your book. Everything Medes adds opens beneath the text, and one gesture closes it again.

    2. Every answer says where it came from.

      From your book General explanation Illustrative
      Each label reflects where the help actually came from. It isn’t decoration.

    3. When it can’t be sure, it shows you the page.

      An honest “not sure” beats a confident wrong answer. If something can’t be grounded, Medes says so and hands you back the original.

    4. Nothing opens on its own.

      No chat window lurking in the corner, and no streaks or badges. You pull, it answers, it folds away. The tutor offers a hint before it gives an answer.

    5. Your library lives with you.

      Books, notes and every layer you open are local files you own. When a model is used, it sees the idea you pulled, not your book.

    Built for two readers at once: the first-year who’s lost but curious, and the specialist who wants the assumptions, the notation, and room to disagree. They make the same gesture and aim it at different depths.

    −5

    Where it stands, honestly.

    This page sketches the Medes we’re building. The app itself is still in the lab. No invented numbers, no borrowed logos.

    Working in prototypes

    • Pulling at any depth, with an exact return to your sentence
    • Shared-state figures: crowd, paths and formula as one case
    • Aiming help at meaning, notation, mechanism and more
    • A local workspace that restores every layer and note
    • A native, GPU-rendered reader study

    Being designed

    • The final reading interface you see sketched here
    • Read in context and evidence comparison for prose
    • PDF and EPUB, with properly typeset math
    • A wider library of reviewed figures across subjects

    On the horizon

    • A small on-device model that picks and fills figures
    • Figures that return as review cards
    • Goal mode: an editable route through books you own

    You’ve reached the floor.

    Coming soon.

    We’re opening Medes to a small group of first readers: students, researchers, and anyone stubborn about understanding things properly.

    Join the first readers

    Tell us what you’re reading. We answer every note.

    ↑ Back to the surface