Quote from: smooth on May 19, 2015, 03:09:49 AM

Quote from: cypherdoc on May 19, 2015, 02:45:31 AM

Quote from: smooth on May 19, 2015, 01:26:43 AM

Quote from: rocks on May 19, 2015, 12:44:51 AM

Quote from: smooth on May 18, 2015, 11:26:02 PM

Correct about diamonds. Incorrect about cryptocurrncies. Fungibility means that units are interchangeable. Bitcoins are not interchangeable as long as they have an identifiable history. And in practice participants such as Coinbase are taking that history into account in evaluating coins and users.

If Coinbase was the processor of BTC, then I would agree with you. But Coinbase is not.

The P2P and mining network is the processor of BTC. The P2P and mining network will always consider BTC to be perfectly interchangeable, 1 BTC is always equal to 1 BTC regardless of history, law or anything else. The P2P and mining network will always consider 1 whitelist BTC to be of equal value to 1 blacklist BTC, and process transactions accordingly. This maintains perfect fungibility.

If you argument is that entities (goverments) will try to make individuals value certain coins (whitelist) more over other coins (blacklist). However if they can dictate usage of bitcoin, they can dictate usage of anything, including Monero. Either way it does not matter though, to the P2P network BTC are all still identical, this is fungibility.

If Bitcoin was not perfectly fungible, then you'd have a situation were the P2P network and the blockchain processes 1 blacklist BTC as somehow equaling less than 1 whitelist BTC. That is impossible with the current network and would require a hard fork.

Well I disagree with your definition, as I explained earlier. Fungibility exists within a social context. If nobody cares about the history of Bitcoins, then they're fungible, but if people do care, they aren't. I have some Bitcoins that were mined by me. I'm not interested in trading them for Bitcoins that for all I know might have been stolen from bitstamp and blacklisted by btc-e or others, or might otherwise cause me problems in the future. Not even for a small premium. That's not fungibility by the accurate definition.

that's your choice. but i expect that you continue to accept USD bills routinely despite them being covered in drug taint.

Sure because literally no one cares or has ever cared about the drug taint on bills. That's not quite true with respect to serial numbers, so there is a bit more of a concern there, but not so much in practice.

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likewise if most of the actors in the Bitcoin system don't care or more importantly understand that tracking tainted addresses makes no sense in light of the fact that UTXO's are what gets joined and split in essentially non-trackable ways then what you decide personally to do doesn't matter.

and this is what i see as happening; at least for the last 6 yrs.

You can't say that no one has ever cared about bitcoin blacklisting, whitelisting, tracking etc. It is unquestionably the case that actors such as Coinbase (which may well be the largest actor in the entire Bitcoin system by reasonable measures) do care about it. It is also clear that discussion and proposals for blackisting, whitelist, etc. have repeatedly occurred, etc. Finally it is certainly the case that the original BitLicense proposal had language about banning tumblers/mixers, etc. (I don't know about the current status).

You can speculate about how that might play out in the future but that is exactly what you are doing (I'm doing so too, I'm just acknowledging more uncertainty about how things will work out).

the way i see it, the market has already beaten down most of your concerns.

yes, there has been lotsa discussion but i'm just looking at the results. and that is that there is no formal blacklisting services that exist yet that i know about. and if there is one, i'm sure it's not significant. do i care when about origin when i buy coins nowadays? no.

also, i view what CB is doing differently. i do believe they are dedicated Bitcoin advocates and know and care deeply about fungibility. it's just that they don't want to go to jail so they track the first hop and i'm sure they'd cooperate with any legal investigation. but that doesn't mean they are in favor of blacklisting. in fact, i'm quite sure they aren't.