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⚖️Understand the Trolley Problem

Walk through every major trolley problem variant and the ethical theory each one stress-tests, then design your own dilemma that isolates a single moral factor.

Foundations~2-week path · 5-8 min/day

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🫁Understand VO2 Max

Trace the oxygen delivery chain from lungs to mitochondria and understand why VO2 max is the gold-standard marker of cardiorespiratory fitness.

Applied~2-week path · 5-8 min/day

⚖️Understand the Trolley Problem

Walk through every major trolley problem variant and the ethical theory each one stress-tests, then design your own dilemma that isolates a single moral factor.

Foundations~2-week path · 5-8 min/day

🚢Understand the Ship of Theseus

Explore the oldest identity puzzle in philosophy. Learn why replacing every plank of a ship — or every cell in your body — forces you to rethink what 'same' actually means.

Foundations~2-week path · 5-8 min/day

🔭Understand the Scientific Revolution

Understand why the Scientific Revolution wasn't just new facts replacing old ones — it was a fundamental shift in what counts as knowledge and who gets to decide.

Foundations~2-week path · 5-8 min/day

⚗️Understand the Periodic Table Beyond Memorization

Stop memorizing the periodic table and start reading it. Learn to predict any element's properties, reactivity, and bonding behavior from its position alone.

Foundations~2-week path · 5-8 min/day

🎯Understand Proof by Induction: The Domino Argument That Works

Build intuition for mathematical induction through the domino analogy and concrete number examples, then prove classic identities and write your own induction proof from scratch.

Foundations~2-week path · 5-8 min/day

🏛️Understand Plato's Allegory of the Cave

Unpack Plato's cave allegory layer by layer — from shadows and prisoners to the sun and the theory of Forms — then write your own allegory for a belief you had to unlearn.

Foundations~2-week path · 5-8 min/day

📈Understand Limits Intuitively Before You Touch Epsilon-Delta

Build a gut-level feel for limits through graphs, tables, and zoom-in experiments — then use that intuition to evaluate tricky expressions and invent your own limit-breaking function.

Foundations~2-week path · 5-8 min/day

🎭Understand Iambic Pentameter

Stop labeling iambic pentameter and start hearing it. Learn to feel the da-DUM pulse in speech and poetry — then write your own lines and break the pattern on purpose.

Foundations~2-week path · 5-8 min/day

💪Understand How Muscles Grow (Hypertrophy Basics)

Cut through gym broscience with actual exercise physiology. Learn what triggers muscle growth at the cellular level — then design your own evidence-based training week.

Foundations~2-week path · 5-8 min/day

📐Understand Eigenvectors and Eigenvalues Without the Algebra Fog

Build geometric intuition for eigenvectors before touching a formula — then compute them, connect them to PCA and PageRank, and build your own mini ranking system from scratch.

Applied~2-week path · 5-8 min/day

🕳️Understand Black Holes Without Spaghetti Confusion

Rethink black holes as curved spacetime — not cosmic vacuum cleaners — using thought experiments, scale comparisons, and the geometry that actually traps light.

Foundations~2-week path · 5-8 min/day

🔷TypeScript Type Narrowing

Replace unsafe `as` casts with control-flow narrowing, discriminated unions, and type predicates — then build a type-safe API client that narrows responses by status code.

Applied~2-week path · 5-8 min/day

🇪🇸Spanish Ser vs Estar

Master the real distinction between ser and estar — identity vs. state — through conversational drills, meaning-flipping adjectives, and a capstone self-description that proves you've internalized both verbs.

Applied~2-week path · 5-8 min/day

🇪🇸Spanish Preterite vs Imperfect

Stop guessing which Spanish past tense to use. Build the aspectual instinct that lets you pick preterite or imperfect in any sentence — then prove it by narrating your own story.

Applied~2-week path · 5-8 min/day

🦀Rust's Ownership Model

Build a working mental model of Rust's ownership system — from stack vs heap intuition through borrow checker mastery — so you can read and write Rust without fighting the compiler.

Applied~2-week path · 5-8 min/day

🧪Property-Based Testing

Go beyond example-based tests — learn to express what your code should always do, then let a framework find the inputs that break it.

Advanced~2-week path · 5-8 min/day

🎵Learn the Circle of Fifths in Music Theory

Stop memorizing the circle of fifths as a poster — start using it as a musical GPS. From key signatures to modulation, each drop turns one slice of the circle into a tool you can hear.

Foundations~2-week path · 5-8 min/day

👂Learn Active Listening Skills

Stop nodding along and start actually hearing people. Learn four concrete listening moves — paraphrase, label, clarify, summarize — and practice each one in real conversations until they become second nature.

Foundations~2-week path · 5-8 min/day

🐳Docker Containers Basics

Build the mental model first, then the commands — from containers vs VMs through images, layers, volumes, and networking to composing a multi-service app.

Foundations~2-week path · 5-8 min/day

🏛️Learn Stoicism Basics

Meet classical Stoicism through Epictetus, Seneca, and Marcus Aurelius — the three disciplines, four virtues, and the logos — then write your own nightly meditation on a worry you actually carry.

Foundations~2-week path · 5-8 min/day

🎲Learn Bayes' Theorem and Actually Use It to Update Beliefs

Update beliefs the way doctors, rationalists, and spam filters actually do — starting with frequency trees, finishing with a real prior-posterior update on a coin you've flipped yourself.

Foundations~2-week path · 5-8 min/day

💻Elixir Pattern Matching

Stop reading `=` as assignment and start using it as Elixir's core flow-control tool — through function heads, guards, and `with` — until you can rewrite a tiny command parser without a single `if`.

Foundations~2-week path · 5-8 min/day

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