Monday, December 23, 2019

Alan Dershowitz's Shaky Use of Occam's Razor

William of Ockham
I often see Occam's Razor invoked in a manner in which it wasn't originally intended and which makes it much weaker than its original intent.

During an interview with Scott Adams, James Altucher invoked this weaker interpretation of Occam's Razor.

Now, Alan Dershowitz has invoked this weaker interpretation after it was first used by a host interviewing him  (Starts at the 5 minute mark).


Personally, I am not impressed with Occam's Razor applied in any situation but the broader way it was applied by Altucher and Dershowitz makes it totally useless.

Here is the best discussion of Occam's Razor, by Philip Gibbs and Sugihara Hiroshi in 1996/1997 in the early years of the internet on The Original Usenet Physics at the University of California Riverside:
Occam's (or Ockham's) razor is a principle attributed to the 14th century logician and Franciscan friar William of Ockham. Ockham was the village in the English county of Surrey where he was born.
The principle states that "Entities should not be multiplied unnecessarily."...
The most useful statement of the principle for scientists is "when you have two competing theories that make exactly the same predictions, the simpler one is the better."
Got that?

When you have two competing theories that make the same predictions (outcome), go with the simplest one.

This is very different from the case where you have two theories making different predictions (outcomes) and saying go with the simplest one.

Gibbs and Hiroshi highlight this other use:
Occam's razor is often cited in stronger forms than Occam intended, as in the following statements. . .
  • "If you have two theories that both explain the observed facts, then you should use the simplest until more evidence comes along"
  • "The simplest explanation for some phenomenon is more likely to be accurate than more complicated explanations."
  • "If you have two equally likely solutions to a problem, choose the simplest."
This second use is very dangerous, which both Altucher and Dershowitz use, and can lead to some very bad conclusions.

Indeed, from my perspective even the first way the principle is used is shaky.

I prefer what I am now naming Probably Einstein's Hammer over Occam's Razor.

Gibbs and Hiroshi explain:
The final word is of unknown origin, although it's often attributed to Einstein, himself a master of the quotable one liner:
"Everything should be made as simple as possible, but not simpler."

1 comment:

  1. My pet peeve: People say "theory" when usually they mean "hypothesis." For example: "Your libertarian theory looks good on paper, but it's never been tested and wouldn't work in the real world."
    A theory---e.g. the Theory of Evolution---has already been tested, subjected to peer review, and undergone the rigors of the Scientific Method, and is generally accepted science.