It seems to me that the notion of expertise can only apply to fields in which there is an established body of knowledge. By that I mean fields in which we have (empirical) grounds for believing our knowledge is at least an approximation or heading in the right direction. Physics...
[edit: sorry, the formatting of links and italics in this is all screwy. I've tried editing both the rich-text and the HTML and either way it looks ok while i'm editing it but the formatted terms either come out with no surrounding spaces or two surrounding spaces] In the latest...
I've noticed that here on Less Wrong people often identify themselves as rationalists (and this community as a rationalist one -- searching for 'rationalist' on the site returns exactly 1000 hits). I'm a bit concerned that this label may work against our favour. Paul Graham recently wrote a nice essay...