In this paper,a principle of direct-proof resolution is presented,by which the theorems are decided and proved just on the basis of educing a simplest tautology from their disjunctive normal forms.

Direct and indirect evidences used in fire investigation;

In our country, Scholars criterion of dividing direct and indirect evidence is against the general rules of logic and can not meet the needs of theory and practice while the criterion of foreign scholars is more scientific and reasonable.

This article aims at a depiction of how the ancient story of "ZhiGong indicts his father" has varied in early Chinese classical works from the perspective of "fact,sign and meaning"Based on an storyline with references in the reality,this story has been developped in multiple narrative orders,from which one can catch a glimpse of various principles of thought at work.