Consensus: What Miners Actually Decide
People say “the miners reach consensus” and picture a vote, like the network taking a poll on what's true. That isn't how it works. Here is what miners actually decide, and what they never touch.
1. The rules aren't up for a vote
First there is a rulebook: the protocol. It defines what a valid transaction and a valid block look like. Signatures have to check out. You can't spend coins you don't have. You can't spend the same coin twice. These rules are fixed, and on BSV that is now literal.
In April 2026 the Chronicle update (activated at block 943,816 on 7 April) finished restoring the original Bitcoin protocol, the last major step after Genesis in 2020. BSV calls the result a “set-in-stone” protocol. So the rulebook isn't just hard to change by custom, it is deliberately locked. Nobody votes a broken transaction into being valid. It either follows the rules or it doesn't.
2. Miners validate. They don't rubber-stamp.
Every miner checks every transaction and block against those rules. If a block contains something invalid, the others reject it, they refuse to build on it, and the cheater's block earns nothing. In Satoshi's words, nodes express acceptance of valid blocks “by working on extending them and rejecting invalid blocks by refusing to work on them.”
3. So what's left to decide? The order.
Valid transactions arrive from all over the world with no shared clock. Sometimes two of them conflict, someone tries to spend the same coin two ways. Each can be valid on its own, but only one can come first. That is the one thing left to settle: the order.
4. The vote is on order, not rules
Here is where “voting” really comes in, and it pays to be precise, because Satoshi did call it a vote. Proof-of-work is “one-CPU-one-vote.” But look at what is being voted on. Not the rules. Not whether a transaction is valid, that is already settled. The vote is on which valid history wins. Miners vote by spending real energy to extend the chain they accept, and the chain with the most work stacked on it is the order the network treats as true. To rewrite history you would have to out-work everyone else combined.
Which history wins?
Two miners found conflicting blocks. One spends Alice's coin to Bob, the other spends the same coin to Carol. Both are valid on their own. Add work to a branch and watch which order the network keeps.
Alice → Bob
Alice → Carol
Even work: the network has no winner yet. Add a block to one side.
5. Why be honest? Because it pays.
None of this runs on good faith. Mining costs real money: hardware, energy, bandwidth. Follow the rules and win a block, you collect the reward. Cheat, and your block is rejected and you eat the cost for nothing. Honesty is simply the profitable move. That is the whole security model: not trust, not authority, only economics pointed the right way.
The catch
That reward is mostly the block subsidy today, and the subsidy is cut in half every four years, heading toward zero. So the thing paying for security is shrinking. What replaces it? That is the security-budget question, and it is why scaling isn't optional.
Follow the economics into Scaling