Entities should not be multiplied unnecessarily.
William of Ockham was a noted English logician of the 14th century. Ockham’s razor is often quoted simply as ‘the simplest explanation is usually the right one.’ This is a gross simplification of a powerful logical tool. A better stating of it would be something like ‘All things being equal, the simplest explanation is more often correct.’ We live in a complex world where the answer to any question is often very complex. All things being equal, with no more evidence for one solution than another, we should not posit the existence of an agent we do not need to explain a phenomenon. When thinking about a subject, we should use the simplest reasoning possible unless the evidence compels us to include an extra agency.
There has been a recent innovation in the world of philosophy which claims to put Ockham’s razor to rest. Scientists are notoriously sniffy of philosophy, and so Mike Alder has created an improvement of Ockham’s razor – Newton’s Flaming Laser Sword. Simply put, this new philosophical tool states ‘That which cannot be settled by experiment is not worth debating.’ The Flaming Laser Sword certainly simplifies things; one thinks Ockham may have approved of it.