Feynman knew physics but he didn't know ornithology. When you name a bird, you've actually identified a whole lot of important things about it. It doesn't matter whether we call a Passer domesticus a House Sparrow or an English Sparrow, but it is really useful to be able to know that the male and females are the same species, even though they look and sound quite different; and that these are not all the same thing as a Song Sparrow or a Savannah Sparrow. It is useful to know that Fox Sparrows are all Fox Sparrows, even though they may look extremely different depending on where you find them.

Assigning consistent names to the right groups of things is colossally important to biology and physics. Not being able to name birds for an ornithologist would be like a physicist not being able to say whether an electron and a positron are the same thing or not. Again it doesn't matter which kind of particle we call electron and which we call positron (arguably Ben Franklin screwed up the names there by guessing wrong about the direction of current flow) but it matters a lot that we always call electrons electrons and positrons positrons. Similarly it's important for a chemist to know that Helium 3 and Helium 4 are both Helium and not two different things (at least as far as chemistry and not nuclear physics is concerned).

Names are useful placeholders for important classifications and distinctions.

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Semantics are important. On the other hand you don't get additional knowledge from getting the name in an additional language that treats the concept with the same semantic borders.

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5lmm5yDid you deliberately pick this example, where Feynman speculated that they might be the same thing? Names are useful as shorthand for a bundle of properties - but only once you know the actual bundle of properties. I sometimes think science should be taught with the examples first, and only given the name once students have identified the concept.
10Epictetus5yI think Feynman's point was that a name is meaningful if you already know the other information. I can memorize a list of names of North American birds, but at the end I'll have learned next to nothing about them. I can also spend my days observing birds and learn a lot without knowing any of their names. I don't think anyone will disagree with this. The hard part, though, is properly setting up the groups in the first place. Good classification systems took years (or centuries) of work and refinement to become the systems we take for granted today. Feynman has been quoted elsewhere criticizing students for parroting physics terminology without having the least idea of what they're actually talking about. There's the anecdote about students who knew all about the laws of refraction but failed to identify water as a medium with a refractive index.

Rationality Quotes Thread March 2015

by Vaniver 1 min read2nd Mar 2015235 comments


Another month, another rationality quotes thread. The rules are:

  • Please post all quotes separately, so that they can be upvoted or downvoted separately. (If they are strongly related, reply to your own comments. If strongly ordered, then go ahead and post them together.)
  • Do not quote yourself.
  • Do not quote from Less Wrong itself, HPMoR, Eliezer Yudkowsky, or Robin Hanson. If you'd like to revive an old quote from one of those sources, please do so here.
  • No more than 5 quotes per person per monthly thread, please.
  • Provide sufficient information (URL, title, date, page number, etc.) to enable a reader to find the place where you read the quote, or its original source if available. Do not quote with only a name.