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Nodes are not 'economic'

The term economic node gained popularity as an attempt to rank the relative importance of nodes in the Bitcoin network. Some nodes, the argument goes, carry more weight than others. The Coinbase node, for example, represents real economic activity and has capital at risk.

This concentrated economic capital, it is reasoned, will be the centre of the network, in a kind of weighted consensus. Any node which doesn't follow them becomes irrelevant, because the economic activity won't follow.

However, there is nowhere in the Bitcoin protocol for economic standing to be signaled. When a node validates a block it has two inputs, the block and its validation rules. Nothing in the validation process reads who produced the block nor what they have at stake. A node doesn't ask, because nothing in validation requires that answer. There is no setting for 'economic' node in the software, and there is nowhere to put one.

The thing the term really refers to is something else: economic operators. Those exist, but their weight belongs to the sphere of business and not the software they run.

Economic operators depend upon nodes

Economic activity is recorded in the present state of the network. No node receives that state from another; each derives it for itself, from the same blocks by the same rules. Each node performs the same computation independently and arrives at the same result. What looks like a shared record is an emergent property.

An economic operator's node has no exemption from this. However much capital stands behind it, it holds the record only by deriving it the way every other node does. Should it change its rules, the network does not follow. It simply computes a different state, and steps outside the record it exists to participate in.

This inverts the assumption. The economic weight said to give such a node influence is precisely what denies it any. A node with nothing at stake can diverge and lose nothing. A node holding customer deposits cannot. The greater the stake, the tighter the binding.

Influence works on people, not the protocol

Economic weight has no sway on the protocol, but has plenty on people. An economic operator can argue, advertise, fund development, apply commercial pressure. This is the only method available to them, because there is no single source of rules to modify. There are only individual operators and the software they choose to run. Even a dominant implementation takes effect one operator at a time, when each chooses to run that version — and that choice is where the refusal lives.

So economic operators can only persuade, one node operator at a time, to alter their software. Persuasion may succeed, but it must be in the open, against people who can simply decline.

Partial success does not produce partial change. It produces division. Those who change their software derive one state; those who don't derive another. There is no threshold at which a minority is carried along, because it isn't a vote, it's a computation each node performs alone.

Every node computes alone

Therefore there are no economic nodes. There are only nodes in the P2P Bitcoin network deriving for themselves the same state as other nodes. Economic operators may persuade node operators to modify the software they run, but no amount of capital exempts them from performing the same computation. Their access to the emergent record rests on what everyone's does — running the rules and getting the same answer.