In recent years model-based reasoning has achieved a certain prominence among logicians and cognitive scientists. Its repute is deserved, notwithstanding that it has some vigorous rivals. Although both model-based and non-model-based systems aim at elucidations of good reasoning, there are certain issues that challenge them equally across the lines of their respective theoretical and methodolog...

Abduction is a methodology of scienti c researches. Peirce showed three types of abduction, and expressed them by one syllogism. Recently various researches on abduction or abductive logic have been developed in the elds of automated reasoning and machine learning. In order to systematically understand such researches and to clearly discuss abduction, this paper classi es abduction into ve type...

ly, the algorithm works as follows: • Start with a complete undirected graph on all variables. • For each pair of variables, see if conditioning on some set of variables makes them conditionally independent; if so, remove their edge. • Identify all colliders by checking for conditional dependence; orient the edges of colliders. • Try to orient undirected edges by consistency with already-orient...

This paper investigates the possibility of performing automated reasoning in probabilistic logic when probabilities are expressed by means of linguistic quantifiers. Each linguistic term is expressed as a prescribed interval of proportions. Then instead of propagating numbers, qualitative terms are propagated in accordance with the numerical interpretation of these terms. The quantified syllogi...

Conditional statements, including subjunctive and counterfactual conditionals, are the source of many enduring challenges in formal reasoning. The language of probability can distinguish among several different kinds of conditionals, thereby strengthening our methods of analysis. Here we shall use probability to define four principal types of conditional statements: SUBJUNCTIVE, MATERIAL, EXIST...

The present study extended the investigation of the belief bias effect in syllogistic reasoning in two ways: (1) The effect was studied under instructions to decide whether conclusions were possible, as well as necessary, given the premises; and (2) the effect was studied for types of syllogism where people rarely endorse the conclusions as well as those (valid and fallacious) where endorsement...

suhrawardi’s logic of the hikmat al-ishraq is basically modal. so to understand his modal logic one first has to know the non-modal part upon which his modal logic is built. in my previous paper ‘suhrawardi on syllogisms’(3) i discussed the former in detail. the present paper is an exposition of his treatment of modal syllogisms. on the basis of some reasonable existential presuppositions and a...

Syllogisms are arguments about the properties of entities. They consist of 2 premises and a conclusion, which can each be in 1 of 4 "moods": All A are B, Some A are B, No A are B, and Some A are not B. Their logical analysis began with Aristotle, and their psychological investigation began over 100 years ago. This article outlines the logic of inferences about syllogisms, which includes the eva...