[simias]

I don't think the parent is a luddite for questioning very emphatic and rather baseless claims. The strawman you build is unwarranted IMO.

Household computers were a thing in science fiction long before they were possible and I don't recall anybody doubting you could eventually transmit movies over the internet in a reasonable amount of time.

Then you continue with the usual hand waving when people point out weaknesses in the bitcoin architecture. Because the last thing we want is for the hype to die and the speculation to crash, am I right?

>If you want to keep middle men in between most things that we could potentially do programmatically, thats cool. I'm on the hype train.

You can do things programmatically without using the blockchain. Actually nowadays I'm pretty sure that for the vast majority of transactions online no human is the loop.

>- low tx rate? not for long

What makes you say that? If you think about segwit/lightning and friends I'll wait until I see them working in practice. I'm still skeptical that these solutions will manage to reach high amounts of transaction without losing the decentralized nature of bitcoin.

>- high computational cost? Security feature. Makes fraud/hacks very expensive. If you think energy conservation is more important, other chains don't have this cost (proof of stake)

You make it sound as if proof of stake was actually a thing. Has any serious blockchain successfully implemented PoS at this point? I know many people are talking about it but it's still very much theoretical as far as I know.

>- high node storage cost? mining fees & block reward more than outweigh this.

I don't understand this argument. Nodes and miners are two different things. If you do serious transactions on the network you should run a full node. Are you saying that people who run full nodes should invest in a mining rig to offset the cost? What if they live somewhere electricity is not cheap enough to turn a profit?

>- no way to reverse transactions? feature. you can always add arbitration / escrow

Yeah by using a... trusted third party. How would you scale this? Well, I can think of a way, you could set up organization who would take a small fee to act as trusted third parties. With a high enough volume of transactions these organizations would have a low incentive of cheating for any given arbitration since loss of trust would mean the end of their business and they could be sued. They could also offer loans and other things the blockchain can't provide on its own. You know, like a bank.

>If you go the traditional route, you will always have a company in the middle, taking their cut or selling you out behind the scenes.

The bitcoin network takes its cut as well and these days it's not exactly cheap. And what do you mean by "selling you out behind the scenes"? Privacy issues?

[teknico]

> Has any serious blockchain successfully implemented PoS at this point?

Decred has, in production for months: <https://docs.decred.org/mining/proof-of-stake/>.

True, it's a hybrid Pow/PoS system, not a pure PoS one, which is indeed probably not workable: <https://docs.decred.org/research/hybrid-design/>.

[brulez]

It's not really clear to me how PoS is providing any security in Decred above that provided by the PoW.

If a single entity is able to get 51% of the hashrate why can't they effectively control which PoS tickets are selected?

Since the overall reward & transaction fees are distributed between both PoS & PoW, it seems to follow that at there will be fewer PoW miners resulting in less overall security vs. a pure PoW protocol.

[DennisP]

Regarding third parties, on a blockchain you don't have to trust them to hold your money. You can set up a 2-of-3 scheme where if the two primaries agree then the third party never gets involved, and if they disagree then the third party decides where the money goes, and only then gets a cut. Advantage: in the absence of a dispute, this system is free.

[simias]

Since when is the blockchain free? You still have to pay a transaction fee.

And with your scheme there's still the problem of how do you scale it? Even if you hope that you'll be able to settle the transaction without disagreement you still have to select a third party "just in case". I can't see working at scale unless you have "professional" third parties with good reputation who will be able to oversee a big number of transactions without being tempted to cheat the system. Why would these third party accept to work for free?

Maybe those parties would accept to be paid only in case of dispute but in this case (if the number of disputes is a very small proportion of all transactions) they'll probably ask for a significant amount of money to break even. You want this third party to be very reputable and hard to corrupt after all, that means that they must have a significant amount of money at stake. You don't want some dude doing it as his weekend project in his basement.

Furthermore the one contesting the transaction will have to be the one who pays the company because how could they force the other one to give money? In turns that means that this neutral third-party becomes biased, it has an incentive to side with whoever paid them to weigh in on the transaction since they've effectively become their customer.

That's kind of my problem with this entire blockchain thing, people are reinventing the wheel, telling everybody they're going to "kill the banks!" but they never stop to wonder why our current system works the way it does. I'm not saying that things are perfect as they are but if you don't learn from past mistakes you're doomed to reproduce them.

[DennisP]

Yes, there's the standard transaction fee, but on Ethereum that would be about a penny. My point is there'd be no fee to the third party, in the absence of a dispute. In that case the third party would do no work. They don't even have to know about the transactions where they're designated "just in case."

The fee when there is a dispute would have to be higher; I'd argue that this isn't terrible, since it gives the primaries a stronger incentive to work things out on their own.

Obviously it would help to have some kind of reputation system for arbitrators. That doesn't necessarily have to be on chain; anything that lets both primaries agree on an arbitrator is fine.

The contract is what forces the payment; the money in question is held by the contract, and if the arbitrator makes the decision, the contract automatically deducts the fee from the held funds and pays it.

You're right that sometimes people ignore why the current system works, but the flip side is dismissing blockchain solutions without first understanding how they work.

[spookthesunset]

> this system is free.

Free? Who pays for the blockchain? Last I looked into it, each transaction requires about enough electricity to power a house for an entire day. That isn't very free.

[DennisP]

That's an average including all the mining rewards, it's not actually paid by people issuing transactions. A simple transaction on Ethereum costs about a penny.

I agree the energy consumption of present-day blockchains is a problem; hopefully proof of stake will fix it.

[Mithorium]

http://www.truthcoin.info/blog/pow-cheapest/

regarding proof of stake

[DennisP]

https://github.com/ethereum/wiki/wiki/Proof-of-Stake-FAQ

for counterarguments