Hard to Vary or Hardly Usable?
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With an account, you can revise, criticize, and comment on ideas.My critique of David Deutsch’s The Beginning of Infinity as a programmer. In short, his ‘hard to vary’ criterion at the core of his epistemology is fatally underspecified and impossible to apply.
Deutsch says that one should adopt explanations based on how hard they are to change without impacting their ability to explain what they claim to explain. The hardest-to-change explanation is the best and should be adopted. But he doesn’t say how to figure out which is hardest to change.
A decision-making method is a computational task. He says you haven’t understood a computational task if you can’t program it. He can’t program the steps for finding out how ‘hard to vary’ an explanation is, if only because those steps are underspecified. There are too many open questions.
So by his own yardstick, he hasn’t understood his epistemology.
You will find that and many more criticisms here: https://blog.dennishackethal.com/posts/hard-to-vary-or-hardly-usable
I think the first question is whether HTV is a real concept (because if real, it is programmable, and via EC to arbitrary precision)
To understand if it’s real, we need to seek counterexamples/ counterarguments, not demand that a program can be written
What would such a program prove ? Not that HTV is real, but also not that we understand something about HTV.
That’s because Deutsch only says : no program = no understanding. That implies having a basic conception programmed can mean that you understand something. Take the season’s example, you could simulate that replacing Gods would not change the fact that they cry but that tears are not the same as rain etc. Granted, this would only be for 1 example, extending HTV to general examples would be needed. But with such basic program, for 1 example theory, we can’t conclude either that we do not understand anything about HTV.
Criticising HTV would anyway be the more important first step. Maybe examples of good theories with some ETV aspects (compared to rejected theories) in them could reveal some more.
Criticising HTV would anyway be the more important first step.
The linked blog post has several criticisms of HTV.
Do you mean "HTV is underspecified by Deutsch" ? But that is not a criticism ? It does not point to a mistake/ contradiction with HTV ?
It’s a criticism. Deutsch says to use HTV but never explains in sufficient detail how to do that.
How is that a criticism ? What mistake does it point out/ argue for ?
The mistake is insufficiency. If someone gives you a recipe for baking a cake but doesn’t specify ingredients or bake time, that’s a problem.
Isn't every theory infinitely underspecified ? Also, I would think that criteria for sufficiency must always be subjective ones (e.g. a working computerprogram cannot be itself a proof of meeting an some objective sufficiency criterium)? So I don't see how insufficiency points to a conflict of ideas/ contradiction
Isn't every theory infinitely underspecified ?
No. For example, the theory of addition is sufficiently specified: we have enough info to implement an algorithm of addition on a computer, then run it, test it, correct errors with it, and so on.
Also, I would think that criteria for sufficiency must always be subjective ones (e.g. a working computerprogram [sic] cannot be itself a proof of meeting an some objective sufficiency criterium)?
No, there are objective criteria.