逻辑系统外的“真”

The “Truth” beyond Logical System

非形式论证有广义与狭义之分,在一个形式逻辑系统外非形式论证应做狭义理解,即不可能前提真并且结论假。而在一个形式逻辑内的可靠性证明中就蕴涵了这种狭义的非形式论证。因此,一个逻辑系统只要证明它是可靠的,那么它就能保证不可能前提真并且结论假的出现。

The term“informal argument” can be used in a broad and a narrow proof.Informal argument should be used in a narrow sense when it is not in the formal logical system, namely, it is impossible that premise is true and conclusion is false.And such kind of informal argument with narrow sense can be contained in a reliable proof in the formal logic.Therefore, if the logical system can be proved as reliable, then it ensures the circs of premise is true and conclusion is that false cannot be set up.