What is Occam’s razor? Occam’s razor is a principle that says if you have two competing ideas to explain something, you should always prefer the simpler of the two. It is named after William of Ockham, but he never called it “Ockham’s razor” himself.
The basic idea behind Occam’s razor is that if you have competing reasons for a situation, you should start by investigating the simplest one first. It doesn’t mean that one reason is correct and the other is wrong. The more complicated reason may be the correct reason. It simply means that you should start investigating with the simplest reason and see where it leads you. It comes down to probability. If you hear hoofbeats going past your door, it is more likely to be a horse than a zebra. It is possible that a zebra is walking past your door, but so many things would have to fall in line for that to be the case that, probability-wise, it is vastly more likely to be a horse. Many conspiracy theories fall under this. The Moon Landing conspiracy, for example. All things considered, it is far more likely that NASA landed on the moon than that they created an elaborate fake with the collaboration of over 600,000 people, the support of the Russians, and all of the other myriad things that would have had to go into a conspiracy. It is not impossible that it was faked, but it is far more likely that it wasn’t. If there are two competing theories, start by investigating the one with the fewest moving parts.
The razor part of Occam’s razor is used to imply a philosophical tool for shaving away any unnecessary ideas or complicated reasons in order to get through the opposing explanations. Don’t add extra moving parts unless the evidence forces you to.
Occam’s razor is named after William of Ockham, although he wasn’t the first person to come up with it. He was a Franciscan friar and philosopher born in a small village called Ockham in England in 1287. He studied theology at the University of Oxford, and he spent his early days after university writing commentary on existing theology. His ideas were not well received and he had to defend himself before the pope, forcing him to go on the run. It is likely that he may have been set up by a rival. He found protection in the court of the Holy Roman Emperor Louis IV of Bavaria, and he spent a long time writing treatises in support of his battle to take complete control of the church. For this, he was excommunicated by the pope. He died in 1347.
Throughout his life, he wrote on many subjects and he often wrote about efficient reasoning. His rule was what came to be known as his razor. If you can explain a phenomenon without assuming many hypothetical reasons, the simpler reason is where you should start. The Latin for this is “Entia non sunt multiplicanda sine necessitate,” which means “Entities must not be multiplied without necessity”. This is the basis for his “razor” idea, but, interestingly, he never used this Latin expression. It cannot be found in any of his writings. He wasn’t the first person to use this idea. It can be found as far back as Aristotle, but he did use it so often that it became associated with him, especially in the years after his death.
It appears to have first been called “Occam’s razor” by a Belgian (at least what is Belgium now) theologian in 1649, almost 300 years after Ockham died. He called it “novacula occami” (the razor of Occam) in his booklet “Philosophia christiana de anima” and he has a critic actually using it against Ockham to argue down his ideas. The Latin phrase that Ockham is credited seems to appear in a similar form in the writing of an Irish theologian called John Punch in 1639 and then later at the end of the 17th century. The expression Occam’s razor entered English in 1852. It was used by Sir William Hamilton in 1852 in his book “Discussions in Philosophy and Literature, Education and University Reform”. He was a philosopher. After he first used it, the phrase started to become popular and was used in countless manuscripts and even textbooks from that point onwards. It became an extremely common expression and way of thinking. It was an idea that fit perfectly with the newly growing field of scientific discovery that always looked to find the truth. Occam’s razor was a perfect scientific starting point for investigating the truth. So, even though he never used the expression, William of Ockham has entered our vernacular. And this is what I learned today.
Sources
https://en.wikipedia.org/wiki/Occam%27s_razor
https://en.wikipedia.org/wiki/William_of_Ockham
https://www.newscientist.com/definition/occams-razor
https://en.wikisource.org/wiki/The_Myth_of_Occam’s_Razor
https://www.aaas.org/taxonomy/term/10/origin-and-popular-use-occams-razor
https://en.wikipedia.org/wiki/Libert_Froidmont
https://en.wikipedia.org/wiki/Sir_William_Hamilton,_9th_Baronet
Photo by Erik Mclean: https://www.pexels.com/photo/razor-and-comb-on-gray-surface-9456811/