Method
The Soviet kruzhok was a small weekly circle: a few students, a blackboard, a pile of problems, and a teacher who refused to perform the solution. Gelfand’s correspondence school, Kolmogorov’s circle, and the Moscow Center for Continuous Mathematical Education (MCCME) all ran on the same wager. You learn mathematics by being stuck in public, writing a complete argument, and coming back to the same hard problem after you have forgotten the trick.
This site is that wager with the furniture removed. Eight rules. Each one is enforced by the page, not by a pep talk.
Every topic opens with unworked attacks, above the books. You try them cold. Getting stuck is the point of the section. Then you read.
A solution stays locked for 20 minutes after you start the attempt. The clock survives a reload. If you open it early in your head by hunting a forum, you have broken the rule the button could not see. Write for the whole twenty.
Core results show the statement and hide the proof. The button says “I wrote a proof” because that is the price of looking.
Five sets, rising. You do not jump to set 5 because set 2 felt slow. Nothing in a set is optional decoration.
The mastery gate asks for a written solution in mathematical prose: hypotheses, construction, estimate, conclusion. An answer key is a check you run after the writeup exists, never instead of it.
Each topic keeps ten problems. When you log a writeup, this browser asks for them again after 1 day, 7 days, and 30 days. A method you cannot redo next month was rented.
Blank page. No notes. Explain the topic out loud as if the person across the table is sharp and impatient. If you stall on a definition, you do not own it yet.
Tier 0 is one resource, labeled watch-once or read-once. It is there to show you the shape of the subject. It is not the study. Close it.
Learn Anything / calculus, linear algebra, and topology are real pages. I read them. They are unsorted link piles: tensor calculus next to sequent calculus, blog posts next to textbooks. There is no page for precalculus; that slug returns “topic not found.” Where a community link was actually good, it is on the ladder with a reason. Where a free course with problem sets was better, that replaced it. A second public curriculum worth knowing is donkuri/learn-mathematics; it is one person’s path, used here as a cross-check, not as orders.