Well, it is irreversible to the extent giving any physical papers to another person is irreversible.

However, the upside of driving your Tesla with a case full of bills is that there's no immutable world-wide distributed record of your transaction making it irreversible.

It's reversible in the sense that the second you leave, I can just claim you never dropped off the cash. AKA I can reverse it.

Bitcoin isn't digital cash, it has different tradeoffs. That implies there are upsides/downsides to all of these factors.

Sure, you could claim that, but if you're doing it at a scale that ultimately matters, then you're only harming yourself. The only kind of people who would be interested in having business with a person mired in such controversies are people you don't want to have business anyway.

Maybe the guy you hired to drive the Tesla just stole all or some of the cash? How would you know?

We can spend all day coming up with slight variations of this scenario where one or the other person is to blame.

In the end, this situation is one of the few things humans have grown really adept at handling. We're (compared to many other things) very good at negotiating complex social situations and teasing out who are getting shafted in a situation, and we have techniques for dealing with it. (Spreading rumours and/or going to the local leader are prominent among them.)

We have set up economic systems based on trust since forever, and they generally work very well. The only times they stop working are when too large authorities get involved. But there are many responses to that that aren't cryptocurrency.

> Bitcoin isn't digital cash

This made me laugh. It's true, but the name literally means "digital cash".

I was expecting the last word of your post to be "public".

Many would see that as an upside. Irreversible transactions are not very desirable to a lot of folks, particularly where it comes to the consumer side of things.

In that case, write them a cheque?

If you don't want irreversible transactions, you don't want bitcoin.

My point is that claiming bitcoin is or isn't inefficient relative to other systems is nonsense. There's simply no comparable system that has the same guarantees as bitcoin, presently or throughout history.

As far as we know, the power cost of bitcoin may very well be the minimum required energy to run an irreversible proof-of-work distributed ledger. Maybe spending 1% of the world's energy to have this public infrastructure is actually a good deal? I really don't know.

> If you don't want irreversible transactions, you don't want bitcoin.

You brought it up as an upside.

> Maybe spending 1% of the world's energy to have this public infrastructure is actually a good deal?

That seems highly unlikely, especially at a time when we don't have negative externalities priced into that energy cost, and we know we're damaging the climate, and given that the only thing it really brings to the table is decentralisation. Which itself is firstly a bit of a sham (mining tends to centralise) and not even that important to the speculators.

If we can conclude it's nonsense to say that other systems are more efficient than BTC because other systems aren't proof of work distributed ledgers, maybe it's also nonsense to say that Teslas are more energy efficient than something with a 6 litre V12 engine, because they don't have a throaty growl or run on petrol.

Back in the world of actual use cases, we can probably put a ceiling on the value of circumventing AML laws without using a non-POW altcoin at well below BTC's current energy cost.

As such thus regulations will occur once normal folks can't get a refund for whatever broken trinket they purchase with Dogecoin or EROS or ETH or ETHC or BSV or Ripple or Stellar or, or do I need to continue?...

I'm off to play in the penny stock section of Yahoo... /s

Of course there is: physics. I hand you a pile of coins/bills, you have it and I don’t. “Bearer” is sufficient information.

That's not really what irreversible transactions means in this context.

What ledger has recorded this transaction? How might a dispute be resolved? What's stopping the receiver from just claiming you never dropped off the cash when you drive back home?

Ah, but if you send money to a bitcoin address the recipient could simply claim the address you sent the bitcoin to wasn't theirs.

And if they can sign a non-repudiable statement that a given address is theirs, they can just as easily sign a non-repudiable receipt when you hand over the cash.

A transaction involves exchanging something (usually a currency) for something else. What you say is that with bitcoin you have proof and irreversibility of payment but the transaction can still go wrong because payment is only one end of the deal. And when the transaction goes wrong you probably wouldn't want a form of payment that is irreversible.

I am not making a claim of whether or not you want irreversible transactions or that they are somehow inherently better than reversible ones.

I am simply pointing out that USD != bitcoin, so the Tesla-driving-cash example is a fundamentally different thing than a bitcoin transaction.

It's like saying "Jeez, it took THAT MUCH energy to get to the Moon? I can drive around the earth a thousand times with that much energy!"

Yes. You can do that. It might be smarter and better for you to do that. But you won't be on the Moon at the end, and there's no way for you to get there unless you take a spaceship.

In this example cars = money, and spaceships = bitcoin.

Often a simple bill of sale is sufficient

"Often" isn't a guarantee.

Turning "often" into "always" is the reason bitcoin exists, and the reason it uses so much energy.

Imagine that you accepted the Bitcoin transfer to sell somebody’s car for them to a known interested buyer, acting as a quick middleman, but then refused or failed to arrange the sale. There is still room to argue about what exactly the “trade” was and whether it was theft. The Bitcoin doesnt simplify resolving it. There were companies filling offices with people to do this exact “scam” years ago in Canada and I never heard of anyone getting punished because there were no contracts or bills of sale to refer to. Having a record of payment (via credit card) didn’t help anyone

The kinds of people who are moving a billion dollars cash and don't want any record it through the traditional financial system have another solution if someone fucks with the deal -- they kill them.

Everyone else will do whatever kind of wire transfer you do for moving a billion dollars.

That is not necessarily a downside.

I've heard driving Teslas is fun

Also, if you accidentally drive 3601 miles, you lose on the transaction :)

Plus the non-instantaneous driving part.

Apparently you haven’t tried to send Bitcoin when it is backed up. In such times, driving the cash across the country would be much faster than waiting for the Bitcoin transaction to clear.

edit: fixed a typo

I have tried this, and the way you resolve it is by raising your transaction fee. This is done with Replace-By-Fee or Child-Pays-For-Parent transactions.

Unless of course you want to send two transactions at the same time.

Good point. You also don't have to pay attention to the Bitcoin transaction the entire time like you do the road. I'm more just commenting on how Bitcoin transactions are anything but "instant".