Occam's razor

The motions o the sun, muin an ither solar seestem planets can be calculatit uisin a geocentric model (the yird is at the center) or uising a heliocentric model (the sun is at the center). Baith wirk, but the geocentric seestem requires mony mair assumptions nor the heliocentric seestem, which haes anly seiven. This was pyntit oot in a preface tae Copernicus' first edeetion o De revolutionibus orbium coelestium.

Occam's razor (an aa written as Ockham's razor an in Laitin lex parsimoniae) is a problem-solvin principle devised bi William o Ockham (c. 1287–1347), who wis an Inglis Franciscan friar an scholastic filosofer an theologian. The principle states that amang competin hypotheses, the ane wi the fewest assumptions should be selectit. Ither, mair complicatit solutions mey ultimately prove correct, but—in the absence o certainty—the fewer assumptions that are made, the better.