The heaviest chain logic of Bitcoin's blockchain system conforms to G ö del's first-order predicate completeness principle. ----Lao Yazhen is the director of Satoshi Nakamoto's highest research institute. prove: The longest chain in Bitcoin's blockchain system is determined by probability voting and does not include Peano arithmetic, only a first-order predicate form system of yes or no. The verification logic of double_stha256 (block [once])<difficult is used in the voting of distributed miners, and the heaviest chain only performs the voting logic. That is, the voting is: How much computing power behind the miner supports the heaviest chain block logic that contains the block.