Eliezer seems to want us to strike out some category of words from our vocabulary, but the category is not well defined. Perhaps a meta-Taboo game is necessary to find out what the heck we are supposed to be doing without. I'm not too bothered, grunting and pointing are reasonably effective ways of communicating. Who needs words ?

Albert and Barry's different usages of the word 'sound' are both perfectly testable. Once they've taken the reasonable and sufficient step of looking 'sound' up in a dictionary, and having identified the two (out of many) possible meanings they were using, then one can go off and test for the presence of pressure waves in the air, while the other tests for auditory perceptions in the humans (and/or other animals doted with hearing) nearest to the event. They can later compare their results and Albert will say 'there was sound according to the definition that I was using (Webster : sound(1) 1a), while Barry can happily agree while saying there wasn't, according to the definition that he was using (Webster : sound(1) 1b). Having got that over, they will go off for a beer at the nearest bar and have a good laugh over that time-travelling guy's not even knowing how to use a dictionary....

Silas, billswift, Eliezer does say, introducing his diagrams in the Neural Categories post : "Then I might design a neural network that looks something like this:"

The primary categorisation is "Threat / Not a threat", and the main categorisation bias is "Better safe than sorry". You'll find that many of your specific categorisation biases are particular examples of that. Examples are : nervousness about your Great Thing being a cult, Asch experiment situations where you have to join the group or stick out from it. Diagram 1b has 'Threat' written all over it.....

To summarise : A storm in a teacup between a pot and a kettle.

Excellent post, however, "But people often don't realize that their argument about where to draw a definitional boundary, is really a dispute over whether to infer a characteristic shared by most things inside an empirical cluster..." Indeed so, but there are other aspects. Humans also have obsessions with (a) how far your cluster is from mine (kinship or the lack of it) (b) given one empirical cluster, how can I pick a characteristic, however minor, which will allow me to split it into 'us vs them' (Robber's Cave). So when you get to discussing whether an uploaded human brain is part of the cluster 'human', those are the considerations which will be foremost.

I sense these 6 essays on cognitive semantics are going to bring us back to transhumanism sooner or later. As of right now, whatever the radial distance from the prototype, and except on the Island of Dr Moreau, you are DEFINITELY human or definitely not, definitely a bird or definitely not. Pluto is DEFINITELY a pla...... whoops.

Thanks for the stuff on typicality, interesting. Just as a side thought, I suspect this has a bearing on Robin's recent post on complexity in political discourse. If one 'plank' of a candidate's position becomes 'typical' of his whole set of ideas, then that gives strength and coherence to Candidate X as a concept.

I'm a little puzzled by all the above. A prediction market is supposed to squeeze out the last drop of (solvent) expert knowledge concerning a given outcome, but voting is a complex and chaotic phenomenon where 'expert knowledge' is thin on the ground or non-existent. If anyone could reliably forecast election results, I think we'd know about it by now. Think weather forecasting, as a comparison. So we're left with, at best, a few people who really believe in their favorite groundhog, and are prepared to place serious money, and others who are prepared to have a flutter on their hunch or their hopes. The result, even ignoring any possible manipulation, looks awfully like a poll of forecasts, distorted by individuals' like of betting and amounts of spare cash as selection biases. Polls of forecasts are less reliable than polls of intentions. And as for Phil, who seems to think not betting is suspect, perhaps Un-American, or perhaps downright criminal, consider that many people have a conservative mindset, don't bet as a general rule, and so just couldn't be bothered. Apart from which, my Dad told me you should work for a living and not to bet, and my Dad is an Authority.

I suppose I should add, for those who are really stuck in maths or formal logic, that changing the definition of a symbol in a formal system is not the same thing as changing the meaning of a word in a language. In fact you can't, individually and as a decision of will, change the meaning of a word in a language. It either changes, as per my previous comment, or it doesn't.