We analyze and compare geometrical theories based on mereology (mereogeometries). Most theories in this area lack in formalization, and this prevents any systematic logical analysis. To overcome this problem, we concentrate on specific interpretations for the primitives and use them to isolate comparable models for each theory. Relying on the chosen interpretations, we introduce the notion of environment structure, that is, a minimal structure that contains a (sub)structure for each theory. In particular, in the case of mereogeometries, the domain of (...) an environment structure is composed of particular subsets of Rn. The comparison of mereogeometrical theories within these environment structures shows dependencies among primitives and provides (relative) definitional equivalences. With one exception, we show that all the theories considered are equivalent in these environment structures. (shrink)

We sketch a general theory of complex objects and their constituents.

A ‘state of affairs’ is understood here as any kind of concrete entity that can play the role of truthmaker. Different ontologies propose different structures of entities to work as ‘states of affairs’ in this sense. Defenders of universals will propose for the role non- mereological structures of universals, objects and times. Defenders of tropes will propose tropes, either with or without universals and objects. Resemblance nominalists will propose primitive ontological facts of resemblance between objects in time. In any of (...) these cases, times are an essential component of a state of affairs. Any ontology of states of affairs, then, should clarify what times are in order to clarify what states of affairs are. An examination of the dominant reductivist conceptions of times shows that these connections have not yet been thought through carefully. In any of the dominant reductivist conceptions, times are entities that either include or describe everything that happens simultaneously at a given instant. Even in some cases they include the description of everything that happens at any time. If one introduce times taken as they are in any of these reductivist conceptions, it will be essential to a state of affairs everything that happens simultaneously with it, or even everything that happens at any time. Under some assumptions the internal relation of every state of affairs with every other state of affairs expands to the internal relation of everything with everything. This is an unhappy theoretical situation that calls for a more careful consideration of some central tenets in our ontology of time. (shrink)

Discusses Armstrong's and Roman Ingarden's ontology, criticises substance ontology, and defends tropes and a field ontology.

Some of the forerunners of quantum theory regarded the basic entities of such theories as 'non-individuals'. One of the problems is to treat collections of such 'things', for they do not obey the axioms of standard set theories like Zermelo- Fraenkel. In this paper, collections of objects to which the standard concept of identity does not apply are termed 'quasi-sets'. The motivation for such a theory, linked to what we call 'the Manin problem', is presented, so as its specific axioms. (...) At the end, it is shown how quantum statistics can be obtained within quasi-set thbeory. (shrink)

The metaphysical concept of continuity is important, not least because physical continua are not known to be impossible. While it is standard to model them with a mathematical continuum based upon set-theoretical intuitions, this essay considers, as a contribution to the debate about the adequacy of those intuitions, the neglected intuition that dividing the length of a line by the length of an individual point should yield the line’s cardinality. The algebraic properties of that cardinal number are derived pre-theoretically from (...) the obvious properties of a line of points, whence it becomes clear that such a number would cohere surprisingly well with our elementary number systems. (shrink)

There are famously two main metaphysics of persistence, namely three and four-dimensionalism. Both yield a particular solution to the so called puzzle of change. I argue that typical three-dimensionalist solutions to the puzzle face insurmountable difficulties even in the simplest relativistic setting, that of Minkowski spacetime.

Many friends of the category of particularised qualities subscribe to the view that particularised qualities have a unique bearer in which they inhere; no such quality then can inhere in two different entities. But it seems that this idea is flawed, for there are apparent counterexamples. An apple’s redness is identical with the redness of its skin, though the apple is distinct from its skin. So it seems that a principle of beareruniqueness has to be modified, maybe by excluding certain (...) unwanted cases. (shrink)

The perception of spatial bodies is at least in part a perception of bodily boundaries or surfaces. The usual mathematical conception of boundaries as abstract constructions is, however, of little use for cognitive science purposes. The essay therefore seeks a more adequate conception of the ontology of boundaries building on ideas in Aristotle and Brentano on what we may call the coincidence of boundaries. It presents a formal theory of boundaries and of the continua to which they belong, of a (...) sort which allows a resolution of certain Zeno-style paradoxes. The theory proves to be applicable not only in the cognitive science field but also in regard to problems relating to the ontology of geographical and geopolitical boundaries. (shrink)

Processes are occurrents that were, are, or will be happening. Moreover, either they endure (i.e., they continue) or they perdure. Stout [11] contends that they endure. His argument – the Change Argument, hereafter – is grounded in the claims that processes may change and that something may change if and only if it endures. I shall argue that the Change Argument does not succeed. In particular, I shall show that, if the Change Argument aims at being neutral between endurantism and (...) perdurantism, then it is invalid. If, instead, his argument rejects the constraint of neutrality in favor of the assumption of endurance theory for processes, then it is valid, but circular. In either case, Stout’s Change Argument fails to establish that processes endure. (shrink)

This volume portrays the Polish or Lvov-Warsaw School, one of the most influential schools in analytic philosophy, which, as discussed in the thorough introduction, presented an alternative working picture of the unity of science.