An ethical framework is needed, since if there is no taxation the current state-model cannot operate.
Bitcoin does not abolish taxation. I am a miner, I get paid for my contribution of processing power, I convert that to USD, and pay for my expenses. I do this all completely on record, I even make some of my decisions about when to sell and when to convert based on the tax consequences. Since I convert to USD I use a bank, all completely legal, traceable auditable (even more than the cash in my wallet). There is nothing new here for the end user except low transaction costs and a protection form printing press inflation, that hardly requires some new morel framework.
You can work under the table in cash you can do it for bitcoin. Try walking into an interview at Honda or Google and telling them you want to be paid off the books, for 90% of the economy, just not going to happen, even if people are paid in BTC.
It's up to individual information and decision to help or not help in his local community. Bitcoin can allow a hoarder that damages even himself in the sight of profit and greed. Hence this brings ultimately a societal change - to a new system?
High infrastructure societies have strong incentives to socialize, and this is usually the most cost efficient way to deal with things like bridge and road maintenance (some here will disagree, but I stand by that position). For these societies taxation is a functional necessity, and so it will continue. Some think a head tax will be used, I personally support a VAT style tax system with higher rates especially for energy, Since the physical side of the economy will still be mostly traceable, but these are policy decisions, not ethical decisions.
Some subset of any economy is a black market, bourgeoisie ethical considerations don't have much say there, and for everybody else we already deal in cash every day, somebody stuffs their mattress with the stuff, or keeps a chest full of gold coins in the cellar, it just doesn't really matter at the end of the day, bitcoin will not change that.