思维模型手册（Mental Models Handbook） vs NUMEN

A tool to boost your thinking and decisions. Includes classic models, clear tips, and real cases for better choices in study, work, and life.

"Not solving math — the moment you start to feel it." NUMEN is not a problem-set app. It's an app for everyone who once gave up on math — and wants to recover the sense of it. ■ A different approach Other math apps: Definition → Formula → Practice → Wrong answer NUMEN: Experience → Pattern → Intuition → Definition You touch with your finger. You drag a slider. You watch values change. Each fraction slice, each function curve, each direction of a negative number — every concept comes alive as moving math, not memorized math. ■ Who is this for? · Middle and high school students who lost the thread · People burned out on classroom-style explanations · Adults who want to understand investing, statistics, or AI · Anyone who wants to feel "I wasn't bad at math — the connections were just broken" ■ What's inside · Interactive lessons you actually touch 33 lessons across 10 phases — sense, relations, change, chance, shape, cycles, limit, slope, accumulation, direction · Intuition first, definition later See the phenomenon, find the pattern, then meet the formal name · 5–10 minute daily sessions Light enough to keep, deep enough to transform · Daily streaks A little, every day — that's how sense rebuilds · Four languages Korean · English · Japanese · Simplified Chinese — every lesson body translated · iPhone · iPad universal · Fully offline No ads. No tracking. No data collection. No internet calls. ■ Why NUMEN? You weren't bad at math. Only the connections between concepts were broken. NUMEN was designed — by hand, with care — to reconnect them. "Oh — I wasn't dumb. The connections were just broken." That moment is what NUMEN is built for. ■ Privacy by design NUMEN collects zero personal information. All progress is stored only on your device. No analytics, no advertising SDKs, no external APIs. ■ Pricing · The app itself — free to download · Phase 1–3 (12 lessons, ≈ 60 min of content) — free · Phase 4–10 (21 lessons) — single one-time in-app purchase, unlocks forever. No ads, no subscription, no renewal. ■ Coming next · More lessons within Phase 5–10 · Personal review / notes screen Begin today. Mathematical sense is not memorized — it is recovered.