Hexagrams form a perfect double-value logic system, in which every hexagram is equal to a true value table. 易卦是一种完备的二值逻辑体系，每一个卦象就是一组真值表。
In two-dimensional presuppositional logic, the evaluation of each sentence contains the truth value of the sentence and the presupposition value of the sentence. 在二维预设逻辑中，每个句子的赋值是二维的，包含句子本身的真值和句子预设的真值。
