Definition

Noun: The principle that the simplest explanation or theory that fits the evidence is the preferred one. It states that one should not make more assumptions than are necessary. This principle is also commonly known as Occam's razor.

Usage

The "law of parsimony" is used primarily in scientific, philosophical, and logical reasoning to guide hypothesis selection and model building. It favors simplicity and elegance, arguing that unnecessary complexity should be avoided.

Examples

• In scientific research, the law of parsimony suggests that if two hypotheses explain the data equally well, the simpler one is more likely to be correct.
• When diagnosing a problem with your car, applying the law of parsimony means you should check the most common and simple causes (like an empty fuel tank) before assuming a complex engine failure.
• The detective followed the law of parsimony, reasoning that the simplest explanation—the suspect being at the scene with a motive—was preferable to an elaborate conspiracy theory.

Advanced Usage

• Philosophical Application: In philosophy of science, the law of parsimony is not a proof but a heuristic or methodological principle that guides theory choice and helps prevent ad hoc explanations.
• Statistical Modeling: In statistics and machine learning, parsimony is a key criterion in model selection, where a simpler model with fewer parameters is often preferred to avoid overfitting the data.

Variants and Related Words

• Occam's razor: The most common synonym for the law of parsimony.
• Parsimony (noun): The quality of being careful with money or resources; extreme unwillingness to spend. In a scientific context, it refers to the principle of simplicity itself.
• Parsimonious (adjective): Unwilling to spend money; stingy. In scientific theory, it describes an explanation that is elegantly simple and economical in its assumptions.

Synonyms

• Principle of simplicity
• Occam's razor
• Principle of economy

Related Idioms/Phrases

• "The simplest explanation is usually the best.": This is a common, informal expression of the law of parsimony.
• "Cutting with Occam's razor": Refers to the act of eliminating unnecessary complexities from an argument or hypothesis.

Noun

1. the principle that entities should not be multiplied needlessly; the simplest of two competing theories is to be preferred