Nonmonotonic conditionals (A |∼ B) are formalizations of common sense expressions of the form “if A, normally B”. The nonmonotonic conditional is interpreted by a “high” coherent conditional probability, P (B|A) > .5. Two important properties are closely related to the nonmonotonic conditional: First, A |∼ B allows for exceptions. Second, the rules of the nonmonotonic system p guiding A |∼ B al...

A large number of common sense assertions such as prototypical properties, obligation, possibility, nonmonotonic rules, can be expressed using conditional logics. They are precisely under the lights because of their great representation power for common sense notions. But representation is only the half of the work: reasoning is also needed. Furthermore, non-monotonic reasoning necessites both ...

Two experiments examined developmental patterns in children's conditional reasoning with everyday causal conditionals. In Experiment 1, a group of pre-, early, young, and late adolescents generated counterexamples for a set of conditionals to validate developmental claims about the counterexample retrieval capacity. In Experiment 2, participants in the same age range were presented with a condi...

A theoretical link between reasoning and mathematical ability has been supported by some recent empirical evidence. We argue that some of this evidence is indirect and measure selection may have influenced this relationship. We report one study in which mathematical ability was measured using a fluency and a calculation measure (Wood-cock Johnson-III, 2001) and reasoning ability was measured us...

This paper proposes a logic that is specially designed to deal with rules and the reasons based on them. Although the logic is inspired by characteristics of legal reasoning, it aspires to be suitable for dealing with other kinds of rule guided reasoning as well. It is characteristic for this logic that rules are treated as individuals rather than as conditionals, and that application of a rule...