Quote from: pooya87 on Today at 04:14:42 AM

Quote from: death_wish on Today at 03:40:48 AM

However, a node that doesn’t see these data is still a full node.

A full node is a software that performs full verification on everything, if it skips any part of the verification then it no longer can be considered a "full node".
Old nodes that do not receive the witness are no longer performing full verification hence they are not full nodes anymore.

That is a matter of semantics, and quite arguable. I disagree. A part of the beauty of Segwit is that it allows non-upgraded nodes to degrade gracefully. They do degrade—but gracefully so. Anyway, would you say the same of a node that hasn’t yet upgraded to validate Witness v1 (P2TR) rules? What about the softfork consensus cleanup before that?

This semantic argument is off-topic for the discussion of POW vs. POS—an issue that I consider to be of prime importance. Thus, I may be reluctant to take this further here.

Quote from: pooya87 on Today at 04:14:42 AM

Quote from: death_wish on Today at 03:40:48 AM

and a pre-Segwit full node can still follow the correct chaintip, without the SPV/light-wallet vulnerability of being misled onto a malicious minority fork.

If PoW were the only metric then SPV clients can also not be tricked into following a "minority fork" with less work since they are capable of validating (and some of them like Electrum already validate) proof of work and follow the chain with the most work.

I flubbed that explanation while trying to squeeze in a comparison of non-upgraded full nodes to light clients. Thanks for the correction.

Quote from: pooya87 on Today at 04:14:42 AM

Keep in mind that when it comes to "longest chain" it is only an argument when everything else is correct. Miners alone don't control bitcoin, both miners and nodes do.
For example if all miners decided to produce 10MB blocks that would make that chain the chain with the most work but it still wouldn't be considered "bitcoin chain" because it breaks consensus rules.

Indeed! I have been trying to hammer that point home to people for years; and it is critical for understanding the POW vs. POS issue.

Compare one of my recent posts in another thread, apropos hereof:

Quote from: death_wish on June 02, 2022, 09:15:49 PM

Miners are essentially paid employees of the Bitcoin network. Their job is security-critical, so they are paid well; but they are neither the bosses nor the owners of the network, and they do not create the network’s value as a first-order cause.

[...]

The security of consensus validation in Bitcoin is independent of miners, for all purposes except for transaction ordering. Miners have a sharply limited function in Bitcoin: BFT agreement on transaction ordering, to prevent double-spend attacks. All other security is provided by the Bitcoin Core node you have running at home on a Raspberry Pi, consuming 10W of electricity at negligible cost.

This is not the case on POS networks. On POS networks, so-called “validators” with high capital stake have total control of the blockchain.

Quote from: pooya87 on Today at 04:14:42 AM

That's the same with SegWit, if all the miners decided to spend a SegWit P2WPKH output without providing any signature, all full nodes would reject that chain regardless of how long that is but the old nodes would accept it which is another proof that they no longer full nodes.

You are, of course, correct about what would happen in that scenario. My point here is—look, hey, we won! Why argue semantics about whether or not a non-upgraded node is a “full node”? Segwit had such high support from people with nodes that the UASF nuclear option would have worked, had it been necessary. We long ago had enough nodes upgraded that the scenario you state above is not of concern, outside the lies and fantasies of Bcashers. Bitcoin won. Enjoy it.

Having won the last war, I suggest that the adage about “fighting the last war” takes here a meaning different than the usual.

Why are we still arguing over the Segwit upgrade (especially when you and I vehemently agree about it!), instead of proactively organizing to defend Bitcoin in the new war?

“Switch to POS” is an attack on Bitcoin, and it is a threat to Bitcoin. On a thread titled “POW vs. POS”, let’s discuss how we should respond to it.