modal logic

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modal logic

n
1. (Logic) the logical study of such philosophical concepts as necessity, possibility, contingency, etc
2. (Logic) the logical study of concepts whose formal properties resemble certain moral, epistemological, and psychological concepts. See also alethic, deontic, epistemic, doxastic
3. (Logic) any formal system capable of being interpreted as a model for the behaviour of such concepts
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.modal logic - the logical study of necessity and possibility
logic - the branch of philosophy that analyzes inference
2.modal logic - a system of logic whose formal properties resemble certain moral and epistemological concepts
formal logic, mathematical logic, symbolic logic - any logical system that abstracts the form of statements away from their content in order to establish abstract criteria of consistency and validity
alethic logic - the modal logic of necessity and possibility and contingency
deontic logic - the modal logic of obligation and permissibility
epistemic logic - the modal logic of knowledge and uncertainty and ignorance
doxastic logic - the modal logic of belief and disbelief
References in periodicals archive ?
In chapters 8 to 13 Aristotle studies syllogisms which consist of two necessary propositions and those which are composed of one necessary proposition and a second which is modally unqualified.
A final concern with the revisionary possible-worlds reduction is whether it can really be reductionistic.(6) Intuitively, it is necessary that some proposition is necessary.(7) Let us apply the possible-worlds reduction of properties to the property of being a necessary proposition. This property would be the function (set of ordered pairs) from possible worlds to the set of necessary propositions.
Nor, if we put any general doubts about the idea of necessary propositions to one side, is it controversial--within the theory of logical probability--that (6|prime~) is necessary.