u perspek - Filozofski fakultet u Splitu

Summary
This book contains two papers arranged in inverted chronological
order. The second is entit1ed Validity of Practical Inference and
it is author’s doctoral thesis (2000.). The first paper, entitled
Imperative logic and dynamic semantics (2004.) contains further
elaboration of the ideas presented in the thesis. The book presents
a development of a system of update semantics for practical logic.
In the broad perspective, the theme deals with an open problem
in the philosophy of social sciences and humanities. It is widely
accepted that reason explanations (rationalizations) provide an
autonomous methodological ground for explaining actions. On
the other hand, the tests of validity for inferences employed in
reason explanations do not coincide in their results. In the second
paper various influential approaches in practical logic have been
compared and evaluated. A way to reconcile contradictory
results of proposed tests of validity has been proposed. The
analysis has shown that consequence relation in practical logic
is not a standard one: the conclusion may be defeated by
addition of a premise. We have chosen the term ‘prima facie
consequence relation’ to denote the non-monotonic property of
consequence relation in practical logic. In order to model this
kind of defeasible reasoning we have used the framework of
dynamic semantics. Throughout the book several systems of
update semantics for practical propositional logic have been
constructed and examined. The second paper presents the system
of Fiat/Est logic, which was intended to cover on the general level
the interaction between two directions of fit (“word to world”
and “world to word” fit) both for sentences and for intentional
states. The first paper treats imperative logic as the basic level of
practical logic. A formal semantics for imperatives is developed
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