Bayesian Epistemology
6 comments
·February 3, 2025andrewgleave
Going to leave this here: https://plato.stanford.edu/entries/popper/#GrowHumaKnow
dotsam
Relatedly, David Deutsch's "Simple refutation of the ‘Bayesian’ philosophy of science"
> By ‘Bayesian’ philosophy of science I mean the position that (1) the objective of science is, or should be, to increase our ‘credence’ for true theories, and that (2) the credences held by a rational thinker obey the probability calculus. However, if T is an explanatory theory (e.g. ‘the sun is powered by nuclear fusion’), then its negation ~T (‘the sun is not powered by nuclear fusion’) is not an explanation at all. Therefore, suppose (implausibly, for the sake of argument) that one could quantify ‘the property that science strives to maximise’. If T had an amount q of that, then ~T would have none at all, not 1-q as the probability calculus would require if q were a probability.
> Also, the conjunction (T₁ & T₂) of two mutually inconsistent explanatory theories T₁ and T₂ (such as quantum theory and relativity) is provably false, and therefore has zero probability. Yet it embodies some understanding of the world and is definitely better than nothing.
> Furthermore if we expect, with Popper, that all our best theories of fundamental physics are going to be superseded eventually, and we therefore believe their negations, it is still those false theories, not their true negations, that constitute all our deepest knowledge of physics.
> What science really seeks to ‘maximise’ (or rather, create) is explanatory power.
https://www.daviddeutsch.org.uk/2014/08/simple-refutation-of...
adrianN
„The sun is not powered by fusion“ actually contains a little information as to the inner workings of the star, so I’m a bit confused by the argument.
Mizza
Thank you for beating me to it. Astounding how those LessWrong dorks were able to revive the corpse of this dead end of epistemology after it was so thoroughly destroyed by Popper. And to what benefit.. sex crimes, massive financial fraud, murder cults and a far right government?
Here's a fun one https://sci-hub.3800808.com/10.1038/302687a0
llm_trw
I never thought I'd see a misunderstanding of what "implies" means in science versus in logic be the fundamental mistake made in a paper on logic for science.
Here's the truth table for implies (if) in logic.
| A | B | If A then B |
|---+---+-------------|
| T | T | T |
| T | F | F |
| F | T | T |
| F | F | T |
This is where you need to add temporal logic so that the scientific understanding of A casually implies B can be represented in logic.
In short the paper does nothing of the sort of what it says it does because it fundamentally uses the wrong tool for the job.
For a wonderful biographical take on this topic try "The theory that would not die-how Bayes'rule cracked the Enigma code, hunted down Russian submarines & emerged triumphant from centuries of controversy" by Sharon McGrayne.
She tells a terrific story with a fascinating large cast of characters including Laplace,Bayes,Fisher,Pearson,Jeffries,Savage,Turing and many others. Engagingly told, highly recommended. Could the takeaway "Do you want to solve a practical problem or do you want scientific rigor?"