A COUNTEREXAMPLE TO MODUS PONENS* T HE rule of modus ponens, which tells us that from an indicative conditional rlf cjJ then 1/1 l, 1 together with its antecedent cjJ, one can infer 1/1, is one of the fundamental principles of logic. 2 Yet, as the following examples show, it is not strictly valid; there are occasions on which one has good grounds for believing the premises of an application of ...

Based on the fully implicational idea, we investigate the interval-valued fuzzy reasoning with multiantecedent rules. First, we construct a class of interval-valued fuzzy implications by means of a type of implications and a parameter on the unit interval, then use them to establish three kinds of fully implicational reasoning methods for the interval-valued fuzzy reasoning with multi-anteceden...

The aim of this paper is to prove that the following two mathematical concepts are equivalent: 1) Fuzzy Preorders which are compatible with an "AND" operation and 2) Fuzzy Consequence Operators (FCO) [8] verifying a finiteness property with respect to that "AND" operation. The role proposed to fuzzy consequences operators is to be a general notion for obtaining approximate consequences from app...

Discussive logics (also called discursive logics) were introduced in 1948 by Stanis law Jaśkowski and constitute the first family of formal paraconsistent logics. The basic mechanism behind discussive logics is as simple as ingenious. Where L is some modal logic and Γ♦ = {♦A | A ∈ Γ}, a discussive logic DL, associated with L, is obtained by specifying the language L of DL and by stipulating tha...

Two experiments pitted the default-interventionist account of belief bias against a parallel-processing model. According to the former, belief bias occurs because a fast, belief-based evaluation of the conclusion pre-empts a working-memory demanding logical analysis. In contrast, according to the latter both belief-based and logic-based responding occur in parallel. Participants were given dedu...

This study examines the problem of belief revision, defined as deciding which of several initially accepted sentences to disbelieve, when new information presents a logical inconsistency with the initial set. In the first three experiments , the initial sentence set included a conditional sentence, a non-conditional (ground) sentence, and an inferred conclusion drawn from the first two. The new...

It is a well-known fact that some criminals follow perpetual methods of operations known as modi operandi. Modus operandi is a commonly used term to describe the habits in committing crimes. These modi operandi are used in relating criminals to crimes for which the suspects have not yet been recognized. This paper presents the design, implementation and evaluation of a new method to find connec...

This paper defends two theses about probabilistic reasoning. First, although modus ponens has a probabilistic analog, modus tollens does not – the fact that a hypothesis says that an observation is very improbable does not entail that the hypothesis is improbable. Second, the evidence relation is essentially comparative; with respect to hypotheses that confer probabilities on observation statem...

In this paper we propose a propositional temporal language based on fuzzy temporal constraints which turns out to be expressive enough for domains –like many coming from medicine– where knowledge is of propositional nature and an explicit handling of time, imprecision and uncertainty are required. The language is provided with a natural possibilistic semantics to account for the uncertainty iss...

A new approach for uncertainty management for fuzzy, rule based decision support systems is proposed: The domain e:z:pert 's knowledge is e:z:pressed by a set of rules that frequently refer to vague and uncertain propositions. Th.e certainty of propositions is represented using intervals {a. bj e:z:pressing that the proposition's probability is at least a and at most b. Methods and techniques f...