That William of Ockham was really onto something, right? His famous statement, “entities should not be multiplied beyond necessity” has been paraphrased into one of the most-quoted heuristics in history:
“All things being equal, the simplest solution tends to be the best one.”
…and stretched even further as:
“Among competing explanations, the simplest is most likely true”
Except… not so much. Distorted variations of Ockham’s Razor have been used as an anti-intellectual blunt instrument in more arguments than I care to count. And he was writing about theology, where even simplicity is no guarantee of… anything. In nature itself, intractable complexity is the rule. Not a moment too soon, Chris Chatham at Developing Intelligence deconstructs the famous friar in Occam’s razor has a double edge.
Albert Einstein updated the saying this way: “Everything should be made as simple as possible, but not one bit simpler.”
UPDATE: Not content to “kick a sacred cow of science” only once, Chris kicks parsimony a second time today with Failures of Reductionism? Level of Analysis Problems in Cognitive Neuroscience. And the main reason I’m linking these two very interesting articles here is so I can find them again. The two posts make a good answer to the glazed-eyes disavowal of natural complexity that is denialism.
Historical note: Occam apparently never said “entities should not be multiplied beyond necessity” in so many words. The closest formulation found in his works is “Numquam ponenda est pluralitas sine necessitate” or “Plurality ought never be posed without necessity.” The saying “Entia non sunt multiplicanda praeter necessitatem” is either from John Ponce of Cork (if we are to believe the English Wikipedia, or Johannes Clauberg, according to the German.
I agree that we can’t assume nature, especially life itself, to be parsimonious. But I still think the principle is a useful guideline to formulating theories, even if it is to be taken cum grano salis.