Abduction in argumentation frameworks

Abstract

This paper studies abduction in abstract argumentation frameworks. Given an argument, an agent verifies whether the argument is justified or not in its argumentation framework. If the argument is not justified in the argumentation framework, the agent seeks conditions to explain the justification state by hypothesising arguments in the universal argumentation framework. We formulate such abductive reasoning in argumentation semantics and provide its computation in logic programming. We also apply abduction to enforcement and simple dialogue games in argumentation frameworks.

Keywords:

• Abduction
• argumentation framework
• explanation

Disclosure statement

No potential conflict of interest was reported by the author.

Notes

1 For instance, we could recognise the existence of the argument: ‘the rise in sea level caused by global warming could reach 90 centimeters in 100 years’, even if we (non-expert) would not know whether it is acceptable or not. Moreover, we can recognise that the argument is attacked by another argument (whose acceptability is also unknown to non-experts): ‘the rise in sea level caused by global warming would be less than 60 centimeters in 100 years’.

2 We do not have the complexity result for because the complexity of deciding whether an argument is undecided or not in is, to the best of our knowledge, unknown in the literature.

3 We consider the so-called conservative type of enforcement in which modification is made without changing the semantics.