What would happen if someone modified Bitcoin’s software to allow more bitcoins to be created than authorized?
They could get their own computer to accept that modification, but that doesn’t mean the other computers on the network have to recognize it....
And here we come to one of Bitcoin’s most important foundations: THE CONSENSUS RULES.
But what exactly are they?
The consensus rules are the set of conditions that determine which transactions and blocks are valid within Bitcoin.
These rules are implemented in the software used by full nodes and make it possible for different participants to verify information using compatible criteria.
WHAT DO THESE RULES ESTABLISH?
Among other things, they determine:
- What conditions a transaction must meet to be valid.
- That the same transaction output cannot be spent twice within a valid chain.
- How many new bitcoins can be created according to the issuance schedule.
- What technical requirements blocks must meet to be accepted.
For example, Bitcoin has a programmed monetary issuance schedule. If someone tries to add a block that creates more new BTC than permitted, that block violates the consensus rules.
Full nodes that apply these rules will reject it, regardless of who produced it.
This shows that Bitcoin's fundamental conditions do not depend on the individual decisions of whoever transmits the information...
BUT WHO ESTABLISHES THESE RULES?
The original rules were incorporated into the design and initial software developed by Satoshi Nakamoto.
Over time, Bitcoin evolved, and some of those rules were modified through processes of development, discussion, and adoption of changes.
However, Bitcoin has no central administrator with the authority to unilaterally modify the rules that everyone must accept.
Developers can investigate problems, write code, and propose modifications... In fact, there is a public mechanism called a BIP (Bitcoin Improvement Proposal).
BIPs make it possible to document proposals technically, explain their rationale, and submit them for community review.
But here is something important: publishing a BIP does not mean that the proposal has been approved or automatically incorporated into Bitcoin.
Changing the consensus rules requires more than writing code or publishing a new version of a program.
It requires an adoption process and, when applicable, an activation process that allows participants to continue operating with compatible rules.
Node operators decide which software to run, while users and other ecosystem participants also influence the practical acceptance of changes.
No developer can single-handedly force the entire network to adopt a change...
SO, ARE THE RULES DECIDED BY A VOTE?
No. And this is a fundamental distinction. In Bitcoin, consensus does not work like an election where each node represents a vote and the option with the most votes wins.
When a node receives a block, it does not check how many computers are for or against accepting it....
It applies the rules implemented by its software.
If the block meets the relevant conditions, it can consider it valid. If it does not, it rejects it.
Therefore, an invalid block does not become valid simply because many participants announce or support it.
Consensus allows independent computers using compatible rules to reach the same conclusions about the validity of information.
This does not require them all to receive the data simultaneously, but rather to be able to evaluate it consistently when they have the same information.
AND WHAT HAPPENS IF SOMEONE DECIDES TO USE DIFFERENT RULES?
They can modify their program or run a version that applies different conditions.
But that decision initially affects only their own node...
If their rules are no longer compatible with those applied by other participants, disagreements may arise about which blocks are acceptable.
That is why modifying the consensus rules is not simply a matter of updating a program: it requires considering compatibility and the adoption of the change across the network.
SO, WHAT SHOULD WE UNDERSTAND?
Consensus rules are not recommendations or decisions negotiated every time a transaction or a block appears.
They are technical conditions implemented by the software and enforced by full nodes when they verify information.
Their importance lies in allowing numerous independent participants to recognize valid data without relying on a central authority....
BUT CHOOSING WHICH RULES TO RUN DOES NOT MEAN YOU CAN IMPOSE THEM ON THE REST OF THE BITCOIN NETWORK...
🧠 Now that we understand where the rules come from and how they are enforced, an important distinction emerges as we continue.
In Bitcoin, some participants verify compliance with these rules, while others compete to produce new blocks.
Although these activities are related, they are not the same.
And that brings us to our next question:
HOW DOES A NODE DIFFER FROM A MINER?....