What is Occam’s Razor? A Short Explanation

(Last Updated On: May 25, 2018)

What is Occam’s Razor?
Occam’s Razor is a principle that can be attributed to 14th-century logician William of Ockham. The principle, translated from Latin, states that “entities should not be multiplied unnecessarily.” For the sake of authenticity, here it is in its original Latin forms:

  • “Pluralitas non est ponenda sine neccesitate”
  • “Frustra fit per plura quod potest fieri per pauciora”
  • “Entia non sunt multiplicanda praeter necessitatem”

So What is Occam’s Razor?

According to the principle of Occam’s Razor, when someone is presented with competing hypothetical answers to a problem, they should select the answer that makes the fewest assumptions.

If you’re finding yourself confused, don’t worry, it’s confusing stuff. To boil it down to the simplest terms, Occam’s Razor is the principle behind the idea that the simplest explanation is usually the right one.

There are two parts that makeup Occam’s Razor:

  1. Plurality: Plurality should not be posited without necessity.
  2. Parsimony: It is pointless to do with more what can be done with fewer.

Occam’s Razor can be applied to various fields and professions throughout the world. When seeing a patient with various symptoms, doctors might use Occam’s Razor to help determine the possible illness. For example, imagine you have the chills, a cough, and fever. Instead of thinking you have some rare disease, a doctor is likely to conclude you have the flu, as that is the most likely, and simplest answer.

Detectives will use Occam’s Razor to deduce who’s the most likely suspect in criminal cases. While not a foolproof system, it typically makes more sense to follow clear evidence, than to believe some complicated cover-up is involved.

William of Ockham

The term “Occam” is actually derived from Ockham, a small town in England. This is where William of Ockham was born. He lived there from about 1285 to 1349.

William was a philosopher and Franciscan monk. He took a vow of poverty, only living with that which was necessary. It is this form of simplicity which is thought to have had a significant influence on his way of thinking about the world.

It is worth noting that William didn’t necessarily invent the ideas behind the principle that would come to bear his name. The basis of Occam’s Razor was already well-established by William’s time. William would, however, present the principle in way that could be understood easily (if you knew Latin). And he would utilized this principle to justify a slew of conclusions, including one of his more well-known statements: “God’s existence cannot be deduced by reason alone.” As you might imagine, this didn’t sit well with the Pope.

Occam’s Razor and Science

Occam’s Razor seems to fit well with the scientific method, in part because simpler theories are preferable to more complex ones, especially when it comes to testing. However, Occam’s Razor proves nothing, so instead, the principle should be applied more as a guide; if faced with two possible explanations for the same thing, the simpler one is usually the correct one.

In a classic example, we can look at the work of physicists Hendrik Lorentz and Albert Einstein. Both came to similar conclusions about the theory of special relativity, however, they had different explanations for them. Lorentz held that wonkiness within the space-time continuum resulted from the influence of ether, a medium that science has proven doesn’t exist. Einstein’s explanations did not reference ether, and hence, his conclusion won out over Lorentz’s as it was simpler.

Today, Occam’s Razor continues to help guide decisions. While not a perfect method, it can be a useful tool to anyone faced with a problem that has multiple possible answers.