Hypothetical plus disjunctive inference takes hypothetical proposition and disjunctive proposition as its premises, out which 12 inference models may be produced.

The application of disjunctive syllogism is indispensable to investigation,which has been proved by investigation practice for a long time.

Whether it is viewed in the light of inference mechanism or from the angle of premise constitution, in essence, dilemma belongs to fullconditioned hypothetical inference, and therefore should observe the rules of hypothetical inference, the socalled argument does not hold water that dilemma belongs to disjunctive syllogism and should observe the latter s rules.

The paper analyzes the contents of exclusive logical thinking,its manifestation in economic activities,and its relationship with the law of excluded middle and disjunctive inference.

The THOG problem was used to study the cognition mechanism of disjunctive reasoning.

The disjunctive reasoning is an important reasoning in the process of detection of crimes.

But the studies about disjunctive reasoning are less than others.

The paper expounds three theoretical problems of the two-difficulty inference: First,demarcation of the connotation of formation and destruction;second,transformation of equivalence of formation and destruction;third,types of premise,and discusses the realistic significance of these three theoretical problems.