Recently, Babbitt columnist Yuan Dao said in the "Rereading the Shuncong Mail Series – Anonymous Articles" that KYC is not needed in the Bitcoin world, at least at the current stage, KYC is not needed, and there is no way to do KYC. There are four reasons for this: First, Bitcoin is a decentralized system developed through a cold start method. Without a leading operation, it cannot find a subject that is responsible for KYC. Secondly, the circulation of Bitcoin as a currency is still relatively rare. More often, it exists as a commodity with certain investment attributes, and KYC is not required to buy or sell goods. Third, convert bitcoin into French currency, or convert French currency into bitcoin. This is the interface and boundary between Bitcoin world and the legal currency world. If Bitcoin requires KYC, then it is more effective on this boundary, and digital currency. Exchanges and traditional banks are just two firewalls on this border. Fourth, KYC is for AML, but now the number of behaviors that use Bitcoin for malicious purposes has been declining due to insufficient bitcoin anonymity.