## Definition **The Second Law as backdrop to human progress** is Steven Pinker's use of the Second Law of Thermodynamics — the statistical tendency of physical systems toward disorder — as a conceptual frame for understanding why human flourishing requires sustained effort and why the Enlightenment project is non-trivial. In *Enlightenment Now* (2018), Pinker argues that entropy is "the most important law for understanding the universe" and that the ordinary difficulty of human life — disease, poverty, ignorance, violence — is not a puzzle requiring explanation but the thermodynamic default from which the Enlightenment has partially and effortfully escaped. This note treats the *social and philosophical application* of the Second Law. For the physical concept itself, see [[Entropy and the Arrow of Time]]. ## The Argument The Second Law states that, in a closed system, entropy — the number of disordered microstates — increases over time. Order is a rare, improbable configuration; disorder is the vast majority of possible states. Therefore, absent directed effort, things tend to fall apart. Pinker extends this reasoning to human affairs: > "Our bodies are improbable assemblies of molecules and they maintain that order with the help of other improbabilities: the scarce substances that can nourish us, and the scarce materials in the scarce forms that can clothe us, protect us, and move things to our liking. Most of the arrangements of matter on Earth are of no use to us, so that when things change without a human agent directing the change, they are likely to change for the worse. The Entropy Law is widely acknowledged in everyday life in sayings like 'Everything falls apart,' 'That's life,' and 'If anything can go wrong, it will.'" The corollary is that wellbeing, health, order, and prosperity are all **improbable, locally low-entropy states** that can only be created and sustained by expending energy and applying knowledge. Poverty, disease, ignorance, and violence are not aberrations; they are what happens by default when the counter-entropic effort of civilisation ceases. ## Energy, Knowledge, and Progress Pinker introduces a **circular link between energy and knowledge** as the engine of progress: - Energy (calories, fuel) enables the cognitive surplus needed to generate knowledge. - Knowledge enables the extraction and use of more energy. - This virtuous cycle accelerated in the Axial Age (surplus calories freed early philosophers), then dramatically again in the Industrial Revolution (fossil fuels freed mass populations from subsistence labour). The key formula, in Pinker's words: "Energy channelled by knowledge is the elixir with which we defeat entropy." ## Implications for the Enlightenment Project Entropy explains three things about the Enlightenment: 1. **Why progress is hard**: creating any form of social order, health system, or knowledge institution is a local reduction of entropy that must be actively maintained. It does not sustain itself. 2. **Why decline is easy**: the withdrawal of effort (institutional collapse, anti-scientific politics, war) immediately allows entropy to reassert itself. Gains are fragile; losses can be rapid. 3. **Why the Enlightenment project is genuinely important**: the ideals of reason, science, and humanism are not pleasant luxuries but the cognitive and institutional machinery that channels human energy toward the maintenance and expansion of improbable wellbeing. ## The Evolutionary Complication Pinker pairs entropy with evolution: human cognitive faculties were adapted for small-group survival, not for reasoning accurately about global populations or long-run statistics. This means that even if energy and knowledge are available, the default human tendency is toward tribalism, magical thinking, and negativity bias — all of which work against the sustained application of Enlightenment methods. Institutions that correct for these biases (free speech, peer review, democratic accountability) are themselves counter-entropic achievements. ## Related - [[Entropy and the Arrow of Time]] - [[The Four Enlightenment Ideals (Pinker)]] - [[Progress as Empirically Measurable (Pinker)]] - [[Humanism (Pinker)]] ## Sources - [[Enlightenment Now (Pinker 2018)]]