「From UTXO to Taproot」 @bitcoincorecn 1、 Overall theme: This is not about 'talking about Taproot', but about reshaping the cognitive model of Bitcoin The true theme of this sharing is not Taproot itself, but rather: Bitcoin has never been an "account system+smart contract platform", But rather a value transfer machine that is composable, verifiable, and has no global state. Taproot just pushed this model to a new stage. ⸻ 2、 UTXO timeline page: What you see is Bitcoin's "time view" Slide：UTXO execution timeline across transactions and blocks The core idea has only one sentence: The execution of Bitcoin is not in the 'account', but in the 'time'. Disassemble it: Each UTXO is a disposable object It can only: • Created (output) • Consumed (input) • No 'balance changes' Only: Old UTXO → New UTXO What does this mean? System thinking model Ethereum's current state (State Now) Bitcoin History Over Time Bitcoin is not maintaining a 'state of the world' But rather maintaining an irreversible causal chain ⸻ 3、 Balance is not a state "is the soul of Bitcoin's worldview Slide：In Bitcoin, balance is not a state — it is a query result This is the most important sentence of the whole game. True meaning: Wallet balance ≠ on chain status Wallet balance= The local calculation result of the UTXO set that you can spend So: Nodes don't care how much money you have Nodes only care about: The UTXO you spent, Whether it exists, whether it has not been spent, and whether it meets the script conditions This brings three key consequences: 1. No global account 2. No balance synchronization 3. Natural parallelization (UTXO verifiable in parallel) This is one of the underlying reasons why Bitcoin can run for 15 years without collapsing. ⸻ 4、 'You're not paying for the address': This is a cognitive correction for 99% of users Slide：You don’t pay an address — you lock to script This sentence has a great impact on people from DeFi/EVM backgrounds. The correct model is: Not: Pay to Address Instead: Lock Value to Script The address is only: The encoding format of ScriptPubKey What truly locks the coin is: • Script Unlocking relies on: • Meet script conditions So what really matters in Bitcoin is not: • Address • Account •balance But rather: Under what conditions is this UTXO allowed to be spent? ” ⸻ 5、 The pages of P2PKH are proving that Bitcoin Script ≠ toy language Slide：Example of BTC Script / P2PKH What you see is the most classic: OP_DUP OP_HASH160 <PubKeyHash> OP_EQUALVERIFY OP_CHECKSIG But what this page really wants to explain is: 1. Bitcoin Script is: • Stack based • Verifiable • Non Turing complete 2. However, it is not weak 3. It is a: Conditional Validation DSL (Domain Specific Language) Not for calculation But rather to constrain spending conditions ⸻ 6、 The Taproot page is the entire 'transition point' Slide： Taproot turns Bitcoin from “signature validation” into “programmable spending conditions” This is a very advanced sentence. Taproot is not essentially: ❌ faster ❌ cheaper ❌ More privacy (just a side effect) The essence of Taproot is: Upgrade 'who can spend money' to Under what conditions can money be spent Taproot did three key things: 1.Key Path • Looks like a regular single signature In reality, it may be complex conditions 2.Script Path（Merkle Tree） Only expose the executed branch • Complete invisibility under other conditions 3. Improvement of Abstract Ability • Multiple signatures • Delay • Condition execution • Covenant (future) This is where Bitcoin truly enters: Programmable, but still verifiable, predictable, and non malevolent ⸻ 7 “Bitcoin Is Not Turing-Complete — By Design” This page is a gentle but fatal comparison to Ethereum Bitcoin intentionally avoids: • Global Status • Loop Variable memory Because: Global state=exponential increase in consensus cost Comparison essence: BitcoinEthereum Core Object UTXOAccount Consensus object transaction status Verifiability Local Global Small attack surface, extremely large In long-term safety experiments ⸻ 8、 Last page: Ethereum as a Live Experiment This is not belittling ETH, but positioning it differently The implicit conclusion of the speaker is: Ethereum is an experimental field for exploring computation Bitcoin is an extremely conservative value protocol •ETH： • Rapid iteration • Continuously repairing • State expansion •BTC： • Slow down • Extreme restraint Once upgraded, it becomes a 10-year level ⸻ 9、 This set of content provides you with practical insights (very important) Based on your previous discussion about BTC, Taproot, assets, and programmable value, there are three key signals: one ️⃣ Bitcoin is taking a 'non EVM programmable route' no •DeFi •World Computer But rather: • Conditional ownership • Time lock Multi path control Offline verifiable logic ⸻ two ️⃣ Real Bitcoin applications won't look like Uniswap But more like: • Insurance • Trust Family Treasury • Conditional inheritance • Separation of hot and cold permissions Multi jurisdictional trusteeship Taproot=Primitive for Digital Trust ⸻ three ️⃣ If you are thinking about the 'next asset form' of BTC This sharing implies: Bitcoin does not require EVM to support complex asset relationships It only needs better 'conditional expression ability' ⸻ 10、 Summarize the entire slide in one sentence Bitcoin is not gradually becoming Ethereum, But it's about the matter of 'money', To achieve the most conservative, robust, and difficult to attack pinnacle in the history of computer science