I summarized what was important to LW readers. I skipped through the parts of the video that most LWers would have found uninteresting (people used to posit theories with unnecessary details called "myths"? who knew?) so I could get to Deutsch's new explanation of explanation which amounts to "unnecessary details are bad" (which are equivalent to "easy-to-vary" aspects).
Yes, you may have found it interesting. It still would have been nice to know the basic form of Deutsch's point before blowing ~15 minutes listening to boring stuff just to get to something that can be restated in a few sentences.
(Modding my appreciated summary down sure helps your argument though.)
I welcome anyone else to blow 20 minutes of their life to confirm my summary.
I hadn't realised that you were taking the karma ratings as indicative of agreement. I didn't vote it down before because I have tended only to use my downvote on stupid or thoughtless comments - not valid comments that disagree with what I think.
Once it became clear that you thought that the votes weren't just appreciating effort but were signalling agreement it would have been dishonest not to vote it down.
I'm sure this talk will be of interest, even if most of the ideas that he talks about will be familiar to readers here.
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In this talk David Deutsch discusses "the most important discovery in human history"; how humanity moved beyond a few hundred thousand years of complete ignorance about the universe. Deutsch attempts to be specific about what led to this change - he concludes that it is the insistence that an explanation be 'hard to vary'.
Whilst a 'hard to vary' explanation is functionally the same as a, more commonly known, Occam's Razor explanation (since fewer parameters necessarily make a fit harder to vary) the slightly different emphasis might be a useful pedagogical tool. A 'hard to vary' explanation will perhaps lead more naturally to questions about strong predictions and falsifiability than Occam's razor. It also seems harder to misunderstand. As we know, Occam's razor suffers because of the difference between actual complexity and linguistic complexity, so an explanation like "it's magic" can appear to be simple. Magic might appear simple, but it will never appear 'hard to vary', so students of rationality would have one less pitfall awaiting them.
Deutsch also touches on what constitutes understanding and knowledge and cautions us not to trust predictions that are purely of an extrapolated empirical nature as there is no true understanding contained there.
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If you haven't already read Deutsch's book "The Fabric of Reality" I'd highly recommend that as well.