[gwern]

> There doesn't appear to be anyway for anyone to know whether I am simply hoarding those Bitcoins to dump on the market at a later date or if they have been permanently removed from the money supply.

Yeah, this is the big problem with the papers or blog posts pointing out how many coins are not moving around and then insinuating that Bitcoin is a scam or that it will soon be destroyed as an old miner dumps a few hundred thousand coins: for most of them, the parsimonious explanation for them not moving is simply that they've been lost. But there's no way to prove this! Did Satoshi wipe his hard drive when he moved on to other 'projects'? We have no way of knowing.

(There apparently are ways to verifiably destroy bitcoins - send them to impossible addresses or something like that - but I haven't heard that anyone has bothered doing that and this wouldn't apply to people losing coins accidentally or apathetically.)