The 180-Day Descent
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About the course

Syllabus

Thirteen blocks, 180 lessons, each building on the day before.

The syllabus is the book's route through the world: not a shelf of unrelated topics, but a sequence of descents where each day gives the next one firmer ground. It begins by asking how belief earns trust, then moves through mathematics, physics, chemistry, life, medicine, mind, artificial intelligence, economics, societies, ethics, and the future.

Every lesson keeps the same internal shape: an accessible entry point, a core model, a live debate, and a walk toward recent research. The frontier is treated with discipline. Claims are marked as established, promising hints, or contested hype; the goal is not to make novelty feel certain, but to show how evidence changes its weight.

Published now

13 of 180 days

Next up

Day 014 · Synthesis: How We Know

Overview

Thirteen blocks at a glance

Each block builds on the ones before it; the height of each segment reflects the number of days it covers.

Select a block to see its lessons.

Every lesson, day by day

Block I · Days 1-14

Foundations of Knowledge & Reasoning

The epistemic toolkit comes first: everything downstream depends on knowing how we justify and calibrate belief.

  1. 001

    What Is Knowledge?

    A stopped clock exposes why justified true belief is not enough for knowledge.

  2. 002

    The Scientific Method & Demarcation

    Hume's problem of induction, Popper's falsifiability, Kuhn's paradigms, and the replication crisis redraw the line between science and its imitations.

  3. 003

    Logic & Valid Inference

    Deduction, induction, and abduction carry different warranties, while validity and soundness separate good form from true premises.

  4. 004

    Probability as Extended Logic

    Bayes' theorem turns evidence into rational belief revision, while e-values reframe statistical testing as bets against a null.

  5. 005

    Causation

    Causal effects are contrasts between interventions, and observational patterns need designs, graphs, or assumptions before they identify causes.

  6. 006

    Statistics & the Art of Not Fooling Yourself

    P-hacking, p-values, confidence intervals, effect sizes, and multiverse analysis show how statistics can protect inquiry from self-deception.

  7. 007

    Information Theory

    Shannon entropy, bits, channel capacity, Maxwell's demon, and Landauer's principle show why information is measurable and why erasing it has a physical cost.

  8. 008

    Complexity & Emergence

    Starlings, slime mold, cellular automata, and Assembly Theory show how simple local rules can generate global order, and why weak versus strong emergence remains unsettled.

  9. 009

    Systems Thinking & Feedback

    A disc on your wall holds a goal against the cold. The same trick, scaled up, can also tip a planet.

  10. 010

    Models, Maps & Idealization

    A perfect map is a useless map. From Borges to digital twins and AI weather, this day asks what a good model is for.

  11. 011

    Heuristics, Biases & Rationality

    Your mind takes shortcuts. Are those bugs in reasoning, adaptive tools, or the shape of a resource-limited mind?

  12. 012

    Networks

    A stranger on the other side of the planet is closer than you think. The question is why.

  13. 013

    Measurement & Units

    How long is a metre, really? The answer has changed four times — and the last change was the strangest.

  14. 014

    Synthesis: How We Know

    Next up

Block II · Days 15-30

Mathematics & Formal Systems

The formal languages in which physical and biological law are written, plus the proven limits of those languages.

  1. 015

    Number

  2. 016

    Prime Numbers & the Riemann Hypothesis

  3. 017

    Geometry

  4. 018

    Algebra & Symmetry

  5. 019

    Functions & Change

  6. 020

    Calculus I: The Derivative

  7. 021

    Calculus II: The Integral & FTC

  8. 022

    Differential Equations

  9. 023

    Chaos & Nonlinear Dynamics

  10. 024

    Probability & Randomness (Formal)

  11. 025

    Statistics for Inference

  12. 026

    Infinity & Set Theory

  13. 027

    Computation & Turing Machines

  14. 028

    The Limits of Formal Systems: Gödel

  15. 029

    P vs NP & Complexity Classes

  16. 030

    Synthesis: Math as a Tower

Block III · Days 31-48

Physics: Classical to Quantum

The behavior of matter and energy, built intuition-first through multi-day relativity and quantum arcs.

  1. 031

    Classical Mechanics: Newton

  2. 032

    Lagrangian & Hamiltonian Mechanics

  3. 033

    Thermodynamics: The Four Laws

  4. 034

    Statistical Mechanics

  5. 035

    Waves & Light

  6. 036

    Electromagnetism: Maxwell

  7. 037

    Special Relativity I

  8. 038

    Special Relativity II: E=mc²

  9. 039

    General Relativity I

  10. 040

    General Relativity II: Black Holes

  11. 041

    Quantum Mechanics I: The Quantum Leap

  12. 042

    Quantum Mechanics II: Superposition & the Double Slit

  13. 043

    Quantum Mechanics III: Entanglement & Bell

  14. 044

    Quantum Interpretations

  15. 045

    Quantum Field Theory & the Standard Model

  16. 046

    The Muon g-2 Story

  17. 047

    Quantum Computing

  18. 048

    Synthesis: The Two Pillars

Block IV · Days 49-62

Cosmology & Astrophysics + DEEP DIVE 1: The Hubble Tension

The universe at large, descending into precision cosmology's biggest crisis.

  1. 049

    The Sky as a Time Machine

  2. 050

    The Cosmic Distance Ladder

  3. 051

    The Expanding Universe

  4. 052

    The Big Bang & the CMB

  5. 053

    DEEP DIVE 1: The Hubble Tension — Two Numbers

  6. 054

    Hubble Tension: The Distance-Ladder Defense

  7. 055

    Hubble Tension: The Early-Universe Camp

  8. 056

    Hubble Tension: TRGB & Independent Methods

  9. 057

    Hubble Tension: Proposed New Physics

  10. 058

    Hubble Tension: Time-Delay Cosmography

  11. 059

    DESI & Evolving Dark Energy

  12. 060

    Dark Matter

  13. 061

    JWST & Early-Universe Surprises

  14. 062

    Astrobiology & Biosignatures

Block V · Days 63-72

Chemistry & Materials

How atoms combine into the stuff of the world and of life.

  1. 063

    The Atom

  2. 064

    The Periodic Table

  3. 065

    Chemical Bonding

  4. 066

    Reactions, Energy & Equilibrium

  5. 067

    Organic Chemistry & the Chemistry of Carbon

  6. 068

    Water & Acids/Bases

  7. 069

    Materials Science

  8. 070

    Superconductivity & a Cautionary Tale

  9. 071

    Green & Computational Chemistry

  10. 072

    Synthesis: From Atoms to Stuff

Block VI · Days 73-92

Biology & Evolution + DEEP DIVE 2: The Physics of Life

What life is and how it might have begun, grounded in thermodynamics.

  1. 073

    What Is Life?

  2. 074

    Evolution by Natural Selection

  3. 075

    The Modern Synthesis & Beyond

  4. 076

    The Cell

  5. 077

    Molecular Machinery: DNA → RNA → Protein

  6. 078

    Proteins & Folding

  7. 079

    Metabolism & Bioenergetics

  8. 080

    Development

  9. 081

    Ecology & Ecosystems

  10. 082

    The Microbiome

  11. 083

    DEEP DIVE 2: Entropy & the Puzzle of Life

  12. 084

    Far-From-Equilibrium Thermodynamics

  13. 085

    Fluctuation Theorems & Landauer's Principle

  14. 086

    Dissipative Adaptation

  15. 087

    Abiogenesis: The RNA World

  16. 088

    Abiogenesis: Hydrothermal Vents & Geochemistry

  17. 089

    Origin of Life: Compartments & Autocatalysis

  18. 090

    Origin of Life: Theories of Life Itself

  19. 091

    The Tree of Life & LUCA

  20. 092

    Synthesis: Life as Physics + History

Block VII · Days 93-116

Genetics, Biotech & Medicine + DEEP DIVE 3: Transgenerational Epigenetics

Heredity to the clinic, with expanded coverage of the body, immune system, and modern medicine.

  1. 093

    Heredity: Mendel to Watson-Crick

  2. 094

    The Genome

  3. 095

    Gene Expression & Regulation

  4. 096

    Epigenetics: The Toolkit

  5. 097

    DEEP DIVE 3: The Two Waves of Reprogramming

  6. 098

    Inter- vs Trans-generational Inheritance

  7. 099

    The Contested Mammalian Cases

  8. 100

    The Takahashi 2023 Test Case

  9. 101

    Protein Folding & Drug Design

  10. 102

    CRISPR & Gene Editing

  11. 103

    Base & Prime Editing

  12. 104

    How the Body Works I: Systems Overview

  13. 105

    How the Body Works II: Heart, Lungs, Blood

  14. 106

    How the Body Works III: Gut, Liver, Kidneys

  15. 107

    The Immune System I: Innate & Adaptive

  16. 108

    The Immune System II: Memory & Vaccines

  17. 109

    Cancer

  18. 110

    Immunotherapy & CAR-T

  19. 111

    Infectious Disease & Pandemics

  20. 112

    Metabolic Science & GLP-1 Drugs

  21. 113

    The Biology of Aging: Hallmarks

  22. 114

    Longevity Interventions

  23. 115

    Partial Reprogramming

  24. 116

    Synthesis: Medicine in 2026

Block VIII · Days 117-130

Brain, Mind & Consciousness + DEEP DIVE 4: Theories of Consciousness

From neurons to the hard problem and the 2025 adversarial-collaboration results.

  1. 117

    The Neuron & Neural Signaling

  2. 118

    Brain Architecture

  3. 119

    Perception

  4. 120

    Memory

  5. 121

    Emotion

  6. 122

    Sleep & Dreams

  7. 123

    DEEP DIVE 4: The Hard Problem

  8. 124

    Global Neuronal Workspace Theory

  9. 125

    Integrated Information Theory

  10. 126

    The Cogitate Adversarial Collaboration

  11. 127

    Higher-Order & Other Theories

  12. 128

    Clinical Consciousness

  13. 129

    Animal & Machine Consciousness

  14. 130

    Free Will & the Self

Block IX · Days 131-146

Intelligence: Cognition & AI + DEEP DIVE 5: AGI/Alignment

Natural and artificial minds, with a fair two-sided AGI debate.

  1. 131

    Cognitive Science

  2. 132

    Heuristics, Biases & Dual Process

  3. 133

    Language & the Mind

  4. 134

    Intelligence: What Is It?

  5. 135

    History of AI

  6. 136

    Machine Learning Foundations

  7. 137

    Deep Learning & Neural Networks

  8. 138

    How LLMs Work

  9. 139

    DEEP DIVE 5: Scaling Laws & Emergence

  10. 140

    Reasoning Models

  11. 141

    Mechanistic Interpretability

  12. 142

    AI Alignment: The Problem

  13. 143

    Deceptive & Scheming AI

  14. 144

    Superalignment & Scalable Oversight

  15. 145

    The AGI Timeline Debate

  16. 146

    Synthesis: Intelligence, Natural & Artificial

Block X · Days 147-158

Psychology, Economics & Money

The human animal individually and in markets, including finance and banking.

  1. 147

    Personality & Individual Differences

  2. 148

    Social Psychology

  3. 149

    The Replication Crisis & Credibility Revolution

  4. 150

    Microeconomics

  5. 151

    Macroeconomics

  6. 152

    Behavioral Economics

  7. 153

    Money: What Is It?

  8. 154

    Banking & Credit Creation

  9. 155

    Central Banking & Monetary Policy

  10. 156

    Financial Markets & Crises

  11. 157

    Inequality

  12. 158

    Crypto & Decentralized Finance

Block XI · Days 159-170

Societies + DEEP DIVE 6: The Deep History of Inequality

Anthropology, deep history, politics, and geopolitics.

  1. 159

    Anthropology & Human Nature

  2. 160

    Deep History & the Ancient-DNA Revolution

  3. 161

    DEEP DIVE 6: The Dawn of Everything I

  4. 162

    Dawn of Everything II: Göbekli Tepe & Seasonality

  5. 163

    Dawn of Everything III: Cities Without Kings

  6. 164

    Dawn of Everything IV: The Critiques

  7. 165

    Political Philosophy

  8. 166

    Comparative Politics & Regimes

  9. 167

    International Relations

  10. 168

    World Order & Geopolitics 2026

  11. 169

    Demography & Migration

  12. 170

    Synthesis: How Societies Hang Together

Block XII · Days 171-176

Meaning: Philosophy, Ethics, Religion, Art

The great questions, applied ethics, and value.

  1. 171

    The Great Questions of Philosophy

  2. 172

    Ethics: Foundations

  3. 173

    Applied & Frontier Ethics

  4. 174

    Religion & the Sacred

  5. 175

    Philosophy of Language & Aesthetics

  6. 176

    Art History & The Meaning of Life

Block XIII · Days 177-180

Forces Shaping the Future + Capstone

Climate, energy, biotech, AI economy, and synthesis.

  1. 177

    Climate Science & Climate Futures

  2. 178

    The Energy Transition & Fusion

  3. 179

    Biotechnology, Biosecurity & the AI Economy

  4. 180

    Capstone: Synthesis & The Open Frontier

What's next

Coming up

The book has published through Day 013. The next lesson is Day 014: Synthesis: How We Know, in Block I. Review the epistemic toolkit; build a personal "confidence calibration" framework to apply for the rest of the course.

  1. Day 014 · Synthesis: How We Know
  2. Day 015 · Number
  3. Day 016 · Prime Numbers & the Riemann Hypothesis
  4. Day 017 · Geometry
  5. Day 018 · Algebra & Symmetry
  6. Day 019 · Functions & Change

After the opening block, the course turns from how we know to the formal languages of knowledge: mathematics, probability, systems, information, and computation. Those tools then do the heavy lifting for the later chapters on physical law, living systems, minds, institutions, and the research frontier.