21 Facts About Philosophical logic

An important issue for philosophical logic is the question of how to classify the great variety of non-classical logical systems, many of which are of rather recent origin.

Deontic Philosophical logic pertains to ethics and provides a formal treatment of ethical notions, such as obligation and permission.

Intuitionistic Philosophical logic is based on the idea that truth depends on verification through a proof.

When understood in a narrow sense, as discussed in this article, philosophical logic is the area of philosophy that studies the application of logical methods to philosophical problems.

Different systems of Philosophical logic provide different accounts for when an inference is valid.

For some, classical logic is too narrow: it leaves out many philosophically interesting issues.

Treatises on modern Philosophical logic often treat these different systems as a list of separate topics without providing a clear classification of them.

Classical logic is not an independent topic within philosophical logic.

Classical Philosophical logic was initially created in order to analyze mathematical arguments and was applied to various other fields only afterward.

The different forms of modal Philosophical logic are often presented as a nested hierarchy of systems in which the most fundamental systems, like system K, include only the most fundamental axioms while other systems, like the popular system S5, build on top of it by including additional axioms.

Deontic Philosophical logic usually expresses these ideas with the operators and.

Just as in alethic modal logic, there is a discussion in philosophical logic concerning which is the right system of axioms for expressing the common intuitions governing deontic inferences.

Temporal modal Philosophical logic can be translated into classical first-order Philosophical logic by treating time in the form of a singular term and increasing the arity of one's predicates by one.

Epistemic Philosophical logic is a form of modal Philosophical logic applied to the field of epistemology.

Dynamic epistemic Philosophical logic is a distinct form of epistemic Philosophical logic that focuses on situations in which changes in belief and knowledge happen.

Intuitionistic Philosophical logic is a more restricted version of classical Philosophical logic.

Free Philosophical logic rejects some of the existential presuppositions found in classical Philosophical logic.

Free Philosophical logic avoids these problems by allowing formulas with non-denoting singular terms.

On this view, classical predicate Philosophical logic introduces predicates with an empty extension while free Philosophical logic introduces singular terms of non-existing things.

Formal semantics of classical Philosophical logic can define the truth of their expressions in terms of their denotation.

Relevance Philosophical logic tries to avoid these cases by requiring that for a true material conditional, its antecedent has to be relevant to the consequent.