The logic of argumentation (LA) is a formalised description of the ways in which humans reason and argue about propositions.
It is used, for example, in computer artificial intelligence systems in the fields of medical diagnosis and prognosis, and research chemistry.
Among other things, this means that LA can support contradiction – proof that an argument is true and that it is false.
If there is evidence that arguments are independent and there is a case for increased confidence when they agree, this is sometimes expressed in additional rules of the form "If A and B then ...".
The process of aggregation and resolution can be represented as follows: T = Resolve[Max{For(Ca,x, Cb,y, ...)}, Max{Against(Ca,x, Cb,y, ...)}] where T is the overall assessment of confidence in a proposition; Resolve[] is a function which returns the single confidence value which is the resolution of any pair of values; For and Against are the sets of arguments supporting and opposing the proposition, respectively; Ca,x, Cb,y, ..., are the confidence values for those arguments; Max{...} is a function which returns the strongest member of the set upon which it operates (For or Against).