Mass attracts mass, energy can be neither created nor destroyed, nothing is faster than light—we call these cosmic certainties “laws” of nature, but the comparison is an insult to physics. Regular laws, the human kind, are broken all the time. Laws of nature, by contrast, are products of induction, patterns of occurrence derived from observation; one solid counterexample would break them for good. They are bolstered by theory but backed by no other authority. Newton won’t punish you for violating his laws.
As the historian of science Lorraine Daston recounts in her fascinating study “Rules: A Short History of What We Live By,” the metaphor of natural laws was popularized in 1644 by Descartes in his treatise “Principia Philosophiae.” It has bothered certain thinkers from the start. The natural philosopher Robert Boyle, a contemporary of Descartes, objected to the notion of rational laws being obeyed by brute matter that was “devoid of understanding and sense.” Today, the term has a creaky ring, even if we might slyly appreciate how it captures the fact that science is an inherently human enterprise.
Civilization of any kind relies on rules about human behavior, but their nature isn’t static. Different eras have forged different types of rules, and seen existing ones in different lights. Laws, which aim for lofty authority, are only one of the flavors of constraint Ms. Daston describes, along with models and algorithms. She draws examples from a range of case studies, including Babylonian math texts, premodern recipes, attempts to reform spelling, the municipal regulations of Enlightenment Paris and casuistry, the medieval method of reasoning that is the source of the term “case study.” She plots them all on several overlapping axes that yield rich comparisons: flexible vs. rigid, general vs. specific, “thick” vs. “thin” (thick rules fold in examples and exceptions, while thin ones anticipate a stable, predictable world).
[This discussion continues. Please feel free to read the entire review.]