Ockham’s Razor

'What can be done with fewer assumptions is done in vain with more.'


William of Ockham was an English monk, philosopher, theologian and probable victim of the Black Death, who provided the scientific method with its key principle 700 years ago.
Ockham’s razor (sometimes spelled Occam's razor) is a principle attributed to the 14th century. The principle states that the explanation of any phenomenon should make as few assumptions as possible, eliminating those that make no difference in the observable predictions of the explanatory hypothesis or theory. The term “razor” refers to the act of shaving away unnecessary assumptions to get to the simplest explanation.
The principle is often expressed in Latin as the lex parsimoniae ("law of parsimony" or "law of succinctness")



“entia non sunt multiplicanda praeter necessitatem,”
which translates to:
“Entities should not be multiplied beyond necessity.”

This is often paraphrased as "All things being equal, the simplest solution tends to be the best one." In other words, when multiple competing theories are equal in other respects, the principle recommends selecting the theory that introduces the fewest assumptions and postulates the fewest hypothetical entities.