Justifying Ockham's razor (Introduction)
by David Turell 
, Tuesday, May 03, 2016, 15:45 (2909 days ago)
An article that points out its justification is conditional. It works well is science where it is used in explaining fixed processes:-https://aeon.co/essays/are-scientific-theories-really-better-when-they-are-simpler?utm_source=Aeon+Newsletter&utm_campaign=e2bcf48d0b-Daily_Newsletter_03_May_20165_2_2016&utm_medium=email&utm_term=0_411a82e59d-e2bcf48d0b-68942561-"Albert Einstein spoke for many when he said that ‘it can scarcely be denied that the supreme goal of all theory is to make the irreducible basic elements as simple and as few as possible without having to surrender the adequate representation of a single datum of experience'. The search for simple theories, then, is a requirement of the scientific enterprise. When theories get too complex, scientists reach for Ockham's Razor, the principle of parsimony, to do the trimming. This principle says that a theory that postulates fewer entities, processes or causes is better than a theory that postulates more, so long as the simpler theory is compatible with what we observe. But what does ‘better' mean? It is obvious that simple theories can be beautiful and easy to understand, remember and test. The hard problem is to explain why the fact that one theory is simpler than another tells you anything about the way the world is.-***-"Einstein and Newton say that science is different - simplicity, in science, is not a matter of taste. Reichenbach and Akaike provided some reasons for why this is so. The upshot is that there are three parsimony paradigms that explain how the simplicity of a theory can be relevant to saying what the world is like:- "Paradigm 1: sometimes simpler theories have higher probabilities.-"Paradigm 2: sometimes simpler theories are better supported by the observations.-"Paradigm 3: sometimes the simplicity of a model is relevant to estimating its predictive accuracy.-"These three paradigms have something important in common. Whether a given problem fits into any of them depends on empirical assumptions about the problem. Those assumptions might be true of some problems, but false of others. Although parsimony is demonstrably relevant to forming judgments about what the world is like, there is in the end no unconditional and presuppositionless justification for Ockham's Razor."-Comment: Long essay. I've not quoted the commentary that leads to the conclusion. We sure used it in medicine.
Justifying Ockham's razor
QUOTE: “This principle says that a theory that postulates fewer entities, processes or causes is better than a theory that postulates more, so long as the simpler theory is compatible with what we observe. But what does ‘better' mean?” -Good question, not to mention the fact that different people seem to observe the same thing differently. While sitting steadfastly on my fence, I have to say that with regard to the god versus godless theories, the godless seems to me to be by far the simpler. Some (for me) unbelievable luck, and the rest follows naturally with no complications. Whereas the complications are endless with a (for me) unbelievable, unknown, unknowable, sourceless mind that creates zillions of solar systems and organisms in unknown ways for unknown reasons, spawning countless more theories about itself, leading to religions with their own countless complications and ramifications.…But Ockham himself would probably have disagreed, and in this particular case, I am certainly not going to say that simpler is ‘better', whatever that means.
Justifying Ockham's razor
by George Jelliss 
, Crewe, Wednesday, May 04, 2016, 22:40 (2908 days ago) @ dhw
Their argument ends: "there is in the end no unconditional and presuppositionless justification for Ockham's Razor". - Surely there is in the end no unconditional and presuppositionless justification for Anything! - Even Euclid had to base his geometry on presuppositions. Definitions, Axioms, Postulates. - Likewise it is impossible to communicate without language. That is the whole problem with philosophy. Particularly of the post-modern variety.
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GPJ
Justifying Ockham's razor
by David Turell , Thursday, May 05, 2016, 02:05 (2907 days ago) @ George Jelliss
George: Their argument ends: "there is in the end no unconditional and presuppositionless justification for Ockham's Razor". > > Surely there is in the end no unconditional and presuppositionless justification for Anything! > > Even Euclid had to base his geometry on presuppositions. > Definitions, Axioms, Postulates. > > Likewise it is impossible to communicate without language. > That is the whole problem with philosophy. > Particularly of the post-modern variety. - Nice to have you back. As I noted in medicine Ockham really helps in a practical way.