Forgetting an Argument

TY - CHAP

T1 - Forgetting an Argument

AU - Rodrigues, Odinaldo Teixeira

AU - Gabbay, Dov M

AU - Baumann, Ringo

PY - 2020/4/3

Y1 - 2020/4/3

N2 - The notion of forgetting, as considered in the famous paper by Lin and Reiter in 994 forget has been extensively studied in classical logic and more recently, in non-monotonic formalisms like logic programming. In this paper, we convey the idea of forgetting to another major AI formalism, namely Dung-style argumentation frameworks. Our approach is axiomatic-driven and not limited to any specific semantics: we propose semantical and syntactical desiderata encoding different criteria for what forgetting an argument might mean; analyze how these criteria relate to each other; and check whether the criteria can be satisfied in general. The analysis is done for a number of widely used argumentation semantics.Our investigation shows that almost all desiderata are individually satisfiable. However, combinations of semantical and/or syntactical conditions reveal a much more interesting landscape. For instance, we found that the ad hoc approach to forgetting an argument, i.e., by the syntactical removal of the argument and all of its associated attacks, is too restrictive and only compatible with the two weakest semantical desiderata. Amongst the several interesting combinations identified, we showed that one satisfies a notion of minimal change and presented an algorithm that given an AF and argument , constructs a suitable AF satisfying the conditions in the combination.

AB - The notion of forgetting, as considered in the famous paper by Lin and Reiter in 994 forget has been extensively studied in classical logic and more recently, in non-monotonic formalisms like logic programming. In this paper, we convey the idea of forgetting to another major AI formalism, namely Dung-style argumentation frameworks. Our approach is axiomatic-driven and not limited to any specific semantics: we propose semantical and syntactical desiderata encoding different criteria for what forgetting an argument might mean; analyze how these criteria relate to each other; and check whether the criteria can be satisfied in general. The analysis is done for a number of widely used argumentation semantics.Our investigation shows that almost all desiderata are individually satisfiable. However, combinations of semantical and/or syntactical conditions reveal a much more interesting landscape. For instance, we found that the ad hoc approach to forgetting an argument, i.e., by the syntactical removal of the argument and all of its associated attacks, is too restrictive and only compatible with the two weakest semantical desiderata. Amongst the several interesting combinations identified, we showed that one satisfies a notion of minimal change and presented an algorithm that given an AF and argument , constructs a suitable AF satisfying the conditions in the combination.

KW - Artificial intelligence

KW - Argumentation

KW - Non-monotonic reasoning

U2 - 10.1609/aaai.v34i03.5662

DO - 10.1609/aaai.v34i03.5662

M3 - Conference paper

VL - 34

SP - 2750

EP - 2757

BT - Proceedings of the 34th AAAI Conference on Artificial Intelligence

PB - AAAI Press

ER -