This question, which was the first to be asked of Satoshi when he shared the whitepaper, has sparked debates, a Bitcoin “civil war,” and a variety of innovative ideas throughout Bitcoin’s lifetime. In this chapter, nostr:npub1h8nk2346qezka5cpm8jjh3yl5j88pf4ly2ptu7s6uu55wcfqy0wq36rpev, nostr:npub1dtgg8yk3h23ldlm6jsy79tz723p4sun9mz62tqwxqe7c363szkzqm8up6m, and nostr:npub1au23c73cpaq2whtazjf6cdrmvam6nkd4lg928nwmgl78374kn29sq9t53j shed light on how Bitcoin is already scaling for global adoption so it can truly become the money of the future.

Below is Giacomo Zucco’s answer, as written in “𝟮𝟭 𝗤𝘂𝗲𝘀𝘁𝗶𝗼𝗻𝘀”:

𝗚𝗶𝗮𝗰𝗼𝗺𝗼 𝗭𝘂𝗰𝗰𝗼’𝘀 𝗮𝗻𝘀𝘄𝗲𝗿:

Bitcoin, as a system, allows for much, much more than just a few transactions per second. Bitcoin, as a digitally scarce asset, can be transacted numerous times and in various ways. So if we want to transact bitcoin in the most expensive possible way, which is also the safest in most use cases, we use the global layer one, the eternal and universal Bitcoin ledger. The ledger is one single, append-only, immutable register of all the participants' transactions that will be forever impossible to reduce and must be downloaded, verified, and stored by every node forever. This process is clearly very expensive and not scalable, so it will primarily serve as a settlement layer for more substantial transactions, which will be required with different kinds of security mechanisms.

Some of these different security mechanisms will still retain a very strong security model, which is not the same as the Bitcoin timechain or blockchain but is still reliable and reasonable in most use cases. For example, a Lightning channel will still give the owner of the keys complete control over the content of the channel. And on a Lightning channel, we can have thousands of transactions per second, without having to use the settlement layer. Therefore, we can achieve good security while facilitating thousands of transactions per second.

However, it's important to note that this provides a different level of security. For example, when using a Lightning channel, we would need to be online occasionally to check that the counterparty will not rob us, which is not the case for on-chain addresses. That said, the on-chain address can be censored or attacked by miners, especially if it's new, while a Lightning channel, even if it's old, can have new transactions happen a few seconds ago, having the same security as a transaction that happened a few months ago. Thus, various risk models are involved. Of course, the cheaper, faster, and more efficient you go, the more you may trade off security — especially the long-term security — for your funds. But this is not always true, as in the aforementioned paradox of mining attacks.

To recap, Bitcoin transactions are not only a few per second. Bitcoin transactions are potentially unlimited in number per second. A very specific subset of these Bitcoin transactions, the on-chain, layer-one settlement transactions, are limited to a few per second. Scaling the entire Bitcoin ecosystem within this limitation involves minimizing the use of these on-chain, layer-one settlement transactions and aggregating the demand for transactions outside the blockchain into fewer, consolidated blockchain settlements. So, we need to aggregate many transactions with a different security model into a few settlement transactions that will happen with this very effective — but very expensive — security model. Additionally, this approach offers other benefits, as the settlement layer has notable privacy and censorship resistance limitations, unlike many off-chain transaction models.

Giacomo Zucco is an Italian technology entrepreneur and a consultant/teacher for the Bitcoin and Lightning Network protocols. He spends his time supporting projects that he feels might be relevant to the future of Bitcoin, be it as an educator, consultant, entrepreneur, maximalist, or troll. Previously, he was involved in GreenAddress, AssoBIT, BlockchainLab, and Bitcoin Magazine. He's currently advancing Bitcoin via BHB Network, 𝘉𝘛𝘊𝘛𝘪𝘮𝘦𝘴, Relai, BCademy, and Notarify.

Stay tuned for an announcement about where you can soon purchase your own copy of “𝟮𝟭 𝗤𝘂𝗲𝘀𝘁𝗶𝗼𝗻𝘀”!👀