A close shave with Occam’s Razor


Is there anything that a 14th century Franciscan Theologian called William of Ockham can teach us today? Why yes, there is indeed. The Latin phrase “entia non sunt multiplicanda praeter necessitateis attributed to him. Its a deeply profound and very significant saying that translates as “entities must not be multiplied beyond necessity”. What this means is that when given a choice between a hideously complex explanation or a far simpler alternative, the simpler choice is usually the right one. This is popularly known as “Occam’s Razor” because you can use it to shave away pointless complexity.

The principle is commonly known as Ockham’s razor but it actually pre-dates him. Variations of this can be traced all the way back to Aristotle.

Now one important thing to appreciate here is that it is not a law. Instead you should think of it as a rule of thumb that usually yields the right answer, so its not a bad tool when you need to work out what is bullshit and what is not. For example if I claim that I’m not human then you are faced with several choices:

  1. My claim is correct, I’m an alien or some other bizarre form of life
  2. I’m nuts
  3. I’m lying

Obviously the 3rd is the simplest option, so Occam’s Razor would suggest that choice is most likely to be the correct one, but option 2 is also a possibility. In other words, it points you to the most probable answer, but does not guarantee that it is right.

Oh yes, one further key point for you to take on board. Its not just about the selecting the simplest choice, but rather is more focused on eliminating pointless complexity. In other words, the simplest option might not be correct because a more complex option accounts for details ignored by the simplest choice. In other words, things might not be as simple as you think they are. Confused? OK, lets try an example. Newtonian mechanics held sway for a long time, but the realization dawned that the universe is not that simple and that something more complex was needed to describe reality, so the more complex enhancements of quantum mechanics and relativity were introduced. While Newtonian mechanics is obviously a simpler choice, Occam’s Razor does not apply. Why? Because, the additional details introduced by quantum mechanics and relativity are far from pointless, we need that degree of complexity to explain reality.

OK, I think you get the idea , so now you can deploy this into your Critical Thinking toolbox to shave away lots of bullshit.

Simplicity is the ultimate sophistication.” – Leonardo da Vinci

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