Occam's Razor

Occam's razor is the principle that, among explanations that fit the evidence equally well, the one that assumes the fewest new entities or the least additional complexity should be preferred. It is named for the fourteenth-century English Franciscan friar William of Ockham, though the underlying preference for simple explanations is older and Ockham himself never phrased it as a single maxim; the Latin tag often attached to him, entities must not be multiplied beyond necessity, was coined by later writers summarising his views. Its philosophical standing is genuinely debated: it is not a law of nature and cannot prove a simpler theory true, only recommend it as the better starting point, and philosophers disagree about whether simplicity is really evidence of truth or merely a practical convenience for working scientists, a live question the Stanford Encyclopedia entry cited here surveys at length.