矛盾律

máo dùn lǜ yāo qiú sī xiǎng qián hòu yī guàn bù néng zì xiāng máo dùn

矛盾律要求思想前后一贯，不能自相矛盾。

The law of contradiction calls for consistency of thought from beginning to the end, and allows no self-contradiction.