Peter Fritz – författare

The notions of necessity and possibility, as well as the notion of a possible world, are ubiquitous in philosophy. Nevertheless, these notions remain controversial. It also remains controversial whether metaphysics requires notions drawing distinctions which are finer than those which can be drawn in terms of necessity and possibility, such as the recently much-discussed notion of grounding. In order to make progress on these debates, this book develops a general framework for theorizing about such intensional notions using the tools of higher-order logic. The Foundations of Modality begins by motivating the use of higher-order logic, and introduces a particularly simple form of higher-order logic. Progress is made on well-trodden territory concerning modality and possible worlds by considering first the question how fine propositions are individuated. Peter Fritz uses both logical results and philosophical arguments to motivate a relatively coarse-grained individuation of propositions. Fritz shows that a number of putative metaphysical notions are ruled out by this theory of individuation. Furthermore, the theory allows the controversial notion of (metaphysical) necessity to be delineated as the broadest necessity, which applies just to the single tautologous proposition. This book also vindicates appeals to possible worlds: First, it shows that if anything plays the theoretical role of possible worlds, then certain propositions do so. Second, it argues that there are in fact the required propositions playing the role of possible worlds; this is shown using the notion of plural quantification over propositions in higher-order logic.

This volume explores the use of higher-order logics in metaphysics. Higher-order logics are natural extensions of the common systems of predicate logic, with a history going back to the very beginnings of formal logic. Such logics are well suited to formalize metaphysical views and arguments. Over the last decade, there has been a resurgence of interest in higher-order metaphysics.Seventeen original essays are grouped under five headings. Three introductory chapters present higher-order languages and motivate their use in metaphysics. Three chapters on pure higher-order metaphysics discuss different options of higher-order languages and logics which may be used in metaphysics. Three chapters on applied higher-order metaphysics consider the application of higher-order logic to various central topics of metaphysics. Three historical chapters trace the development of higher-order logic as it relates to metaphysics over the last 150 years. The volume concludes with a discussion, containing two chapters criticizing the use of higher-order logic in metaphysics, as well as responses to these criticisms by two authors.

Propositional quantifiers are quantifiers binding proposition letters, understood as variables. This Element introduces propositional quantifiers and explains why they are especially interesting in the context of propositional modal logics. It surveys the main results on propositionally quantified modal logics which have been obtained in the literature, presents a number of open questions, and provides examples of applications of such logics to philosophical problems.

Propositional quantifiers are quantifiers binding proposition letters, understood as variables. This Element introduces propositional quantifiers and explains why they are especially interesting in the context of propositional modal logics. It surveys the main results on propositionally quantified modal logics which have been obtained in the literature, presents a number of open questions, and provides examples of applications of such logics to philosophical problems.

Groundwater is an increasingly important resource to human populations around the world, and the study and protection of groundwater is an essential part of hydrogeology - the subset of hydrology that concentrates on the subsurface. Environmental isotopes, naturally occurring nuclides in water and solutes, have become fundamental tools for tracing the recharge, history, and contamination of groundwater.