How true is Occam’s Razor? Posted on December 15, 2012 by thebigqs 8 comments Is there logic behind it? Does it make sense? Can it be seen in reality? Share this:TwitterFacebookLike this:Like Loading... Related tagged with Occam's razor Theory
Yes, it is eminently logical. Yes, it is primarily pragmatic. Yes, people repeatedly use it because it works and usually requires the least effort to implement.
Hi Mike, sorry for the delayed reply. I thought Sean was going to wade in and argue against. But for my part I completely agree that it is logical and useful, even if not in every case. I guess the biggest problem is interpretation. It’s meant to be the simplest answer, and some would say that means things like a divine creator. I wouldn’t, because such propositions open up more scientific and philosophical problems than they solve, and are thus complicated.
Yes sorry for my tardiness also, wading doesn’t usually wait on invitations, but since I got one, my gumboots are going to be all over this…..
Occam’s razor is stupid! It is possibly the sutpidest of all philosophical theories! It is so stupid that it almost gives philosophy a bad name……like love in a bon jovi song.
Occams razor = If we don’t know the truth, but have two competing explanations of equal validity, we should chose the simplest one.
Rewind to pre-Darwinian days…..
Why are there animals and plants on earth?
A: because God created and designed them
B: because originally there were single celled organisms and over millions of years these organisms adapted to their environments in a process known as “survival of the fittest”. Eventually these organisms evolved into multi-celled organisms, then primitive life-forms, and then intelligent life forms.
Which is the simplest? A.
Which turned out to be correct? B.
So the supposed logic of Occam’s razor is that the simpler explanation has more chance of being correct. Why?
The only conclusion that I can come to is that an argument with fewer premises has less chance of one of those premises being incorrect.
But on the other hand, having fewer premises means the argument has more chance of being incomplete.
So how can you measure one risk against the other?
I don’t think you can, and therefore there is no reason to favour a shorter explanation over a longer explanation.
I may agree with Mike’s comment that working according to Occams’ razor requires less effort to implement, but so does stupidity and that is hardly a worthwhile reason to call something a valid theory or law (of Parsimony)!
This is exactly what I meant about interpretations and ambiguities. You see evolution actually has far less assumptions than a supernatural deity creating all things from nothingness, even though He exists so it wasn’t nothing… Hopefully you get my point.
But let me give a better example of how Occam’s Razor can almost always be used to argue both sides. Max Tegmark proposed that, somewhere within an infinite stack of parallel worlds, everything that can exist does. Elaborating on these sorts of ideas often leads to what Rees described as “local by-laws” existing within each verse, rather than there being one set of universal laws of physics. Now this sounds like a blatant violation of Occam’s Razor right? Some critics argue just that. But Tegmark points out that amongst the almost infinite mathematical possibilities the idea that everything exists i.e. every possibility is realized rather than just one, can actually be simpler than something. A set of all integers is easily described. But how do you explain the existence of just a specific subset? It would be like a choice between on the one hand accepting every number between 1-100, and on the other accepting a small set of prime numbers chosen by random coin tosses.
No I disagree…
Arguments put forth by those who believe in a God do not contain more assumptions than Evolution. Believers have only two assumptions, 1. God exists. 2. I have faith in his existence. Leading to their circular conclusion that Therefore God exists because I have faith that he does.
Of course if you and I were to try to set out the assumptions required to prove God exists then of course we would have far more, but it is not us who are trying to make the case.
So religious believers pre-darwin had two assumptions, and Darwins theory had a good deal more.
Occams Razor/Law of Parsimony would have driven you to the wrong conclusion.
Tegmarks proposal may be unique in that he is trying to explain the infinite. Using Occams razor would be almost ironic…
As an aside, I really think the phrase “violation of Occams’ razor” is grotesque! You make it ound as though it is a physical law, rather than a pea-brained rule somebody came up with in order to decide between swings and roundabouts.
Occam’s Razor doesn’t apply just because someone’s too stupid to see beyond 2 assumptions. It applies to the assumptions taken, irrelevant of whether the person making a judgement actually sees them. And the creation myth requires beliefs and assumptions that not only neglect the laws of science but actually break them, and with no evidence. And it’s the latter which is key. Pre-Darwin evolution took a lot of assumptions because there was no proof. Today evolution is almost infinitely more simple than the creation myth because it’s been proved!
So you are arguing for or against Occams razor?
As a guide Occam’s Razor is very useful. As a law it completely falls down. That’s basically what I’d argue. I wrote a more intelligent response but lost it, lol.
Nonetheless though, I probs should justify the above. So here goes…
Roughly speaking, Schrödinger’s cat proposes that quantum superposition is the combination of all the possible states of a system. In other words all quantum combinations are possible. And the more you know about quantum physics the more you know that it doesn’t really ever get that simple.
So let’s hold Schrödinger’s cat up to Occam’s Razor.
Ockham’s principle states that the explanation of any phenomenon should make as few assumptions as possible, eliminating those that make no difference in the observable predictions of the explanatory hypothesis or theory. It’s expressed in Latin as lex parsimoniae (law of parsimony). “Entia non sunt multiplicanda praeter necessitatem” is roughly translated as “entities must not be multiplied beyond necessity”. So right from the start we can see that it would be far too simple to say Occam’s razor is all about simplicity.
But surely the following definition is still accurate? When multiple competing theories are equal in other respects, the principle recommends selecting the theory that introduces the fewest assumptions and postulates the fewest entities. Is this definition correct? Actually not entirely, no. Occam’s razor is not concerned with the simplicity or complexity of a good explanation as such. It only demands that the explanation be free of elements which have nothing to do with the phenomenon (and the explanation). Also known as the “the Rube Goldberg antithesis”.
Bringing it back to the initial topic we see that Schrödinger’s cat and Occam’s Razor are each the product of conjecture. They both break down when subjected to substantiated fact. When the box is opened, the quantum superposition collapses and is replaced by fact. This is also true with Occam’s Razor. When a specific phenomenon is pinned-down, the possible/probable explanations give way to procedure. And yet even so these procedural facts fall on both side of the fence, since one could always argue that some assumptions are bigger and more numerous, when another might simply disagree. So is it useful in every sense and for every purpose? No. Is it important nonetheless? If it were not we would not be having this discussion.