Drawing on the principles of human society and the composition of the computer Internet, expand Bitcoin's UTXO model to build a more complex and powerful blockchain world. -Mirror world: human society and the computer Internet world are mirror images of each other, both composed of individuals and shared parts. -Building principles of blockchain: building a blockchain world needs to follow the principles of individual freedom and shared communication of human society/computer Internet. -The UTXO model of Bitcoin: The UTXO individual calculation model of Bitcoin follows the above principles, but is too simple and only applicable to simple calculations and indexing of currency. -Extended UTXO: UTXO is similar to the individual privacy of human beings or the individual terminal of computers, and it can expand the higher level value world based on computer Internet by expanding UTXO. -The significance of Bitcoin: As the third most fundamental mirror world, Bitcoin provides us with the freedom to explore a broader world of value.