you said:
Decentralisation is the way in which participants in the network can effectively reach all other participants in the network as quickly as possible. Such that consensus can be reached with minimal opportunity to have your message (tx) blocked, or otherwise obfuscated.
I replied:
According to that definition, Facebook is highly decentralized.
Then you say:
If you think my definition of decentralised applies to Facebook you didn’t really understand it. As eloquent and well thought out your post, it boils down to exactly what I said. At first glance it’s easy to think decentralisation is X. You just listed all the reasons why people think that.
Facebook allows you to reach all other participants in the network as quickly as possible with your message, there is immediate consensus that this was indeed your message and in as much as your message is in agreement with the "protocol", it will not be blocked or otherwise obfuscated. This is why I said that if that's what your definition is about, Facebook satisfies it perfectly.
This is, however, not the communication problem a crypto currency needs to solve. In fact, a crypto currency needs to solve the INVERSE problem: how to avoid that you can obfuscate, hide your message or give YOU the opportunity to otherwise deny participants in the network to learn about your message.
A crypto currency needs to solve the problem of global non-repudiation, not of divulgation !Indeed, what you, as a user of a crypto currency, would actually want, is that you can send a message to SOME participants, while hiding that message from other participants. If you want to buy a car with bitcoin, you would like the car salesman to learn about your message (your transaction). But you would like to hide that message to the jewellery shop, and you'd like to send a similar message to the jewellery shop, making them believe you can spend your coins again. The whole machinery of bitcoin is such that, no matter how you try, you cannot hide the fact that you sent a message to the car salesman.
The solution that all crypto currencies have, is that there is
some form of collective, unique repository/database where these messages have to be registered, and which can be consulted by all participants, in such a way that nothing can be erased from that repository, or at least, that the effects of that message cannot be reversed in that repository.
And then, there's the battle of how we secure this repository against erasure. How do we make a repository such that once a message is inside, it cannot be removed. How can we make sure that all LATER participants in the system will be made aware of the message that you sent, even if you want to avoid that by all means ?
In fact, if we would have such a system, in which we can register messages for all participants, which cannot be erased,
that's all we actually need. In such
a universal scribble book, we could invent all kinds of tokens, of which we can determine that we transact them with a digital signature. Everyone could invent his own token. I could invent the dinofelis token, and you can have my dinofelis token number 1 against a pizza, with the declaration that I'll never emit another dinofelis token number 1. In as much as people value the dinofelis token number 1, which is now unique (I cannot put a message in the scribble book to emit another one: it is clear to everyone that that second one is bogus and in contradiction with what I said before), you, who sold me a pizza against that token, can transact it with your signature, for a pancake. I wonder whether the dinofelis token number 1 would rise a lot in value, honestly. But bitcoin's creator restricted enormously the liberty to write stuff in that universal scribble book, and invented rules to make dinofelis tokens, the only ones that one can transmit on the scribble book he invented. He invented a lot more rules: when the scribble book will be updated, who decides, and so on.
And this is where my notion of decentralisation comes in: the whole set of rules, the people who can decide what goes into the scribble book and what not, and so on, becomes
a matter of power. You're not emitting your own token. The rules of power decide who emits tokens.
That said, it is this funny formalisation in "rules" that have tricked people into thinking it is worth something - and given that it is now a Keynesian beauty contest, it IS worth something. If one would have set up just a scribble book in which my dinofelis token number 1 was registered, it still wouldn't have taken on any value in the market. Nobody cares about that. The whole marketing around the notions "currency" and "coin" and so on were sheer brilliant. But they also implied "power". Power to obtain goods and services. Power to deny goods and services. Like any power structure.
If you think about it, it is entirely crazy. Anyone out there can start a scribble book. Anyone out there can invent different rules. There is strictly no reason why one would spend a fortune to have a token in one scribble book, while a token in another one doesn't cost much, and if you want to, you can invent your own of which you are the master, and it cost you nothing. This is the purest form of recursive belief system, or, if you want to, the biggest greater fool game in the world. A token in a scribble book is, a priori, worth nothing, because you can, if you want to, make your own scribble book. But given the fact that it has now been proven that people value it, you can bet on the fact that others might value it too. So even if YOU don't value it, others do (and even if they don't, they know that other others do....). You may buy it against genuine value, just to hope to sell it to a greater fool. Because it is in THIS scribble book, and not in THAT scribble book.
Nobody believes a bitcoin is actually worth anything, but everybody believes that he will find someone who believes he will find someone who will accept it against value, just to pass the hot potato to someone else. Too bad for the last one in the row.