Occam's Razor

Philosophical Position
Occam's Razor (or rarely but more accurately Ockham's Razor) is a philosophical position which can be expressed in several ways, including the following:


 * The simplest explanation is probably the correct one.
 * When seeking to explain a phenomenon, choose the hypothesis which requires the fewest postulates.
 * Demonstration by fewer postulates or hypotheses (in short from fewer premises) is ceteris paribus superior; for, given that all of these are equally well known, where they are fewer, knowledge will be more speedily acquired, and that is a desideratum. (Aristotle, from Analytica Posteriora).
 * We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances. Therefore, to the same natural effects we must, so far as possible, assign the same causes (attributed to Isaac Newton).
 * Keep It Simple, Stupid (used as a design principle).

Also known in Latin as the lex parsimoniae (which translates as the law of economy or law of succinctness).

It has profound philosophical implications, and considerable scope for misuse.

In his own words:
 * entia non sunt multiplicanda praeter necessitatem (entities must not be multiplied beyond necessity), or:
 * pluralitas non est ponenda sine necessitate (plurality should not be posited without necessity).

He was not the first to voice this philosophy (see the quote from Aristotle above, for example).