Scientific Laws
Scientific laws are the general principles that science treats as governing or describing nature, and their analysis is a central problem in the metaphysics of science.
Definition
A law of nature is a true, general principle that is not merely accidentally true, that supports counterfactuals, and that underwrites explanation and prediction; competing theories disagree on what makes a generalization lawlike.
Scope
This topic covers regularity (Humean and best-system) accounts, the necessitarian account of laws as relations among universals, dispositional and capacities-based views, and the distinction between genuine laws and accidental regularities, including the role of counterfactual support and ceteris paribus laws.
Core questions
- What distinguishes laws from accidentally true generalizations?
- Are laws mere regularities or relations of necessity?
- Do laws support counterfactuals, and why?
- How should ceteris paribus laws in the special sciences be understood?
Key concepts
- lawhood
- Humean supervenience
- best-system analysis
- nomic necessitation
- counterfactual support
- ceteris paribus law
Key theories
- Best-system (Humean) account
- On the Mill-Ramsey-Lewis view, laws are the theorems of the deductive system that best balances simplicity and strength in describing the world's regularities.
- Necessitarian (DTA) account
- Dretske, Tooley, and Armstrong hold that a law is a relation of nomic necessitation between universals, which explains why laws support counterfactuals.
- Anti-fundamentalist view
- Cartwright argues that fundamental laws are literally false when read as universal claims, and that explanatory work is done by local models and capacities.
History
The Humean regularity tradition was refined into the best-system analysis by Mill, Ramsey, and Lewis. In 1977 Dretske, Tooley, and Armstrong independently proposed the necessitarian account; Armstrong's 1983 book is its canonical statement, while Cartwright's 1983 critique questioned whether fundamental laws are even true.
Debates
- Regularity versus necessity
- Humeans analyse laws as components of the best systematization of regularities, while necessitarians argue only a primitive nomic relation can explain laws' modal force and counterfactual support.
Key figures
- David Lewis
- David Armstrong
- Fred Dretske
- Michael Tooley
- Nancy Cartwright
Related topics
Seminal works
- armstrong1983
- cartwright1983
Frequently asked questions
- What is the best-system analysis of laws?
- On the Mill-Ramsey-Lewis approach, the laws are the regularities that appear as axioms or theorems in whichever true deductive system of the world achieves the best combination of simplicity and informativeness. Lawhood is thus a matter of a regularity's place in the optimal systematization, not of any extra necessity in nature.