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Comment by dudeicus on Occam's Razor · 2011-03-23T15:25:47.821Z · LW · GW

Occam's Razor is "entities must not be multiplied beyond necessity" (entia non sunt multiplicanda praeter necessitatem)

NOT "The simplest explanation that fits the facts."

Now thats just purely definition. I think both are true. I think there are problems with both. The problem with Occams razor, is that yes its true, however, it doesn't cover all the bases. There is a deeper underlying principle that makes Occams razor true, which is the one you described in the article. However summing up your article as "The simplest explanation that fits the facts" is also misleading as in, while it does seem to cover all the bases, it only does so if you use a very specific definition of simple which really doesnt fit with everyday language.

Example: Stonehenge, let me suggest two theories, 1. it was built by ancient humans, 2. it fell together through purely random geological process. Both theories fit with the facts, we know that both are physically possible (yes 2. is vastly less probable, ill get to that in a second). Occams razor suggest 2. as the answer, and "The simplest explanation" appears to be 2. also. Both seem to be failing. The real underlying principle as to why Occams razor is true, is statistics, not simplicity. Now dont get me wrong, I understand why "The simplest explanation that fit the facts" actually points to 1., but then you have to go through this long process of what you actually mean by simplest, which basically just ends up being a long explanation of how "simple" actually means "probable".

Anyways, I'm just arguing over semantics, I do in fact agree with everything you said. I just wish there was no Occams razor, it should just be "The theory which is the most statistically probable, is usually the right one." This is what people actually mean to say when they say "The simplest explanation that fits the facts."

Comment by dudeicus on Occam's Razor · 2011-03-23T14:58:57.737Z · LW · GW

shanerg is right, Occam's razor is not "The simplest answer is usually the right one." It is, "do not suggest entities for which there are no need".

That is a common misrepresentation of Occam's razor, and it is extremely vague and I think it shouldn't be used, it has too many hidden assumptions. Now I do agree with everything that was written in the article, but everything in the article was the underlying explanation for why Occam's razor is true, which simply put, has to do with statistics. I was disappointed though, that this article that was about Occam's razor, didn't actually have Occam's razor in it.

Comment by dudeicus on Occam's Razor · 2011-03-23T14:50:04.423Z · LW · GW

Science is just a method of filtering hypothesis. Which is exactly what Occam's razor is. Occam's razor is not a philosophy, it is a statistical prediction. To claim that Occam's razor is not a science would be to claim that statistics is not a science.

Example: You leave a bowl with milk in it over night, you wake up in the morning and its gone. Two possibly theories, are one, your cat drank it, or two, someone broke into your house, and drank it, then left.

Well, we know that cats like milk, and you have a cat, so you know the probability of there being a cat is 1:1, and you also know your cat likes to steal food when your sleeping, so based on past experience you might say the probability of the cat stealing the milk is 1:2, so you know theres two high probabilities. But when we consider the burglar hypothesis, we know that its extremely rare for someone to break into our house, thus the probability for that situation, while being physically possible, is very low say 1 in 10,000. We know that burglars tend to break into houses to steal expensive things, not milk from a bowl, thus the probability of that happening is say 1 in a million.

This is Occams razor at work, its 1/1 1/2 vs 1/10,000 1/1,000,000. Its statistics, and its science. Nothing I described here would be inaccessible to experimentation and control groups.