Roberto Casati

The project of a 'naive physics' has been the subject of attention in recent years above all in the artificial intelligence field, in connection with work on common-sense reasoning, perceptual representation and robotics. The idea of a theory of the common-sense world is however much older than this, having its roots not least in the work of phenomenologists and Gestalt psychologists such as K hler, Husserl, Schapp and Gibson. This paper seeks to show how contemporary naive physicists can profit from a knowledge of these historical roots of their discipline, which are shown to imply above alla critique of the set-theory-based models of reality typically presupposed by contemporary work in common-sense ontology [1].

This paper is concerned with certain ontological issues in the foundations of geographic representation. It sets out what these basic issues are, describes the tools needed to deal with them, and draws some implications for a general theory of spatial representation. Our approach has ramifications in the domains of mereology, topology, and the theory of location, and the question of the interaction of these three domains within a unified spatial representation theory is addressed. In the final part we also consider the idea of non-standard geographies, which may be associated with geography under a classical conception in the same sense in which non-standard logics are associated with classical logic.

What are the relationships between an entity and the space at which it is located? And between a region of space and the events that take place there? What is the metaphysical structure of localization? What its modal status? This paper addresses some of these questions in an attempt to work out at least the main coordinates of the logical structure of localization. Our task is mostly taxonomic. But we also highlight some of the underlying structural features and we single out the interactions between the notion of localization and nearby notions, such as the notions of part and whole, or of necessity and possibility. A theory of localization—we argue—is needed in order to account for the basic relations between objects and space, and runs afoul a pure part-whole theory. We also provide an axiomatization of the relation of localization and examine cases of localization involving entities different from material objects.

The project of a naive physics has been the subject of attention in recent years above all in the artificial intelligence field, in connection with work on common-sense reasoning, perceptual representation and robotics. The idea of a theory of the common-sense world is however much older than this, having its roots not least in the work of phenomenologists and Gestalt psychologists such as Kohler, Husserl, Schapp and Gibson. This paper seeks to show how contemporary naive physicists can profit from a knowledge of these historical roots of their discipline, which are shown to imply above all a critique of the set-theory-based models of reality typically presupposed by contemporary work in common-sense ontology.

Considering topology as an extension of mereology, this paper analyses topological variants of mereological essentialism (the thesis that an object could not have different parts than the ones it has). In particular, we examine de dicto and de re versions of two theses: (i) that an object cannot change its external connections (e.g., adjacent objects cannot be separated), and (ii) that an object cannot change its topological genus (e.g., a doughnut cannot turn into a sphere). Stronger forms of structural essentialism, such as morphological essentialism (an object cannot change shape) and locative essentialism (an object cannot change position) are also examined.

Ordinary reasoning about space—we argue—is first and foremost reasoning about things or events located in space. Accordingly, any theory concerned with the construction of a general model of our spatial competence must be grounded on a general account of the sort of entities that may enter into the scope of the theory. Moreover, on the methodological side the emphasis on spatial entities (as opposed to purely geometrical items such as points or regions) calls for a reexamination of the conceptual categories required for this task. Building on material presented in an earlier paper, in this work we offer some examples of what this amounts to, of the difficulties involved, and of the main directions along which spatial theories should be developed so as to combine formal sophistication with some affinity with common sense.

This paper proposes a methodological strategy to investigate the question of the individuation of the senses both from a commonsensical and a scientific point of view. We start by discussing some traditional and recent criteria for distinguishing the senses and argue that none of them taken in isolation seems to be able to handle both points of views. We then pay close attention to the faculty of hearing which offers promising examples of the strategy we pursue of combining commonsense and science. In particular, we argue in favour of a distinction between two kinds of modes of presentation associated with sound perception: a mechanical mode of presentation that makes sounds perceptible by other modalities than audition such as touch and a tonal mode of presentation that makes people conceive of sounds as the proper objects of auditory perception.

Consider the following argument If panpsychism is true, then the hard problem of consciousness is solved Physicalism is true Physicalism entails panpsychism. We conclude that The hard problem of consciousness is solved. This is a valid argument, and one whose conclusion has a certain appeal. What about the premisses? How exactly is panpsychism a solution to the problem of phenomenal consciousness? Who can take panpsychism seriously, and how can panpsychism be entailed by physicalism? A little forcing is assumed in suggesting to consider a philosophical argument whose conclusion is panpsychism. But I think the exercise is worthwhile, provided we spell out all the consequences of forcing.

This issue of The Monist is devoted to the metaphysics of lesser kinds, which is to say those kinds of entity that are not generally recognized as occupying a prominent position in the categorial structure of the world. Why bother? We offer two sorts of reason. The first is methodological. In mathematics, it is common practice to study certain functions (for instance) by considering limit cases: What if x = 0? What if x is larger than any assigned value? Physics, too, often studies the (idealized) initial and boundary conditions of a given system: What would happen in the case of a perfect sphere, or a perfectly black body? In the cognitive sciences, research often thrives on the analysis of cognitive errors, perceptual illusions, brain pathologies. Also in logic one can learn a lot by studying special, anomalous scenarios such as those exhibited by the paradoxes: it is unlikely that we actually find ourselves in a soritical context, or in a liar-like situation, but the fact that we might—or simply the fact that we can conceive of such a possibility—is important enough to deserve careful consideration. In short, the odd, the unfamiliar, the extra-ordinary, the limit cases are perfectly at home in scientific and more broadly intellectual discourse at various levels, where they can be fruitfully engaged in a sophisticated way (witness the existence of specific confining and managing strategies for dealing with them); and they are important precisely because they instruct us concerning the normal, the obvious, and the paradigmatic. The same goes for metaphysics, we submit. Although its major concern is, naturally, with such core entities as substances, properties, or hunks of solid matter, a lot may be learned by paying attention to those limit cases where we find ourselves dealing with entities of much lesser kinds, whether real or putative.

Classically, truth and falsehood are opposite, and so are logical truth and logical falsehood. In this paper we imagine a situation in which the opposition is so pervasive in the language we use as to threaten the very possibility of telling truth from falsehood. The example exploits a suggestion of Ramsey’s to the effect that negation can be expressed simply by writing the negated sentence upside down. The difference between ‘p’ and ‘~~p’ disappears, the principle of double negation becomes trivial, and the truth/falsehood opposition is up for grabs. Our moral is that this indeterminacy undermines the idea of inferential role semantics.

Holes are a good example of the sort of entity that down-to-earth philosophers would be inclined to expel from their ontological inventory. In this work we argue instead in favor of their existence and explore the consequences of this liberality—odd as they might appear. We examine the ontology of holes, their geometry, their part-whole relations, their identity and their causal role, the ways we perceive them. We distinguish three basic kinds of holes: blind hollows, perforating tunnels, and internal cavities, treating these uniformly as immaterial bodies. We develop a morphology of holes, focusing on the way a hole can be filled, and then look at the main properties of the resulting conceptual framework: holes are parasitic upon the surfaces of their hosts; holes can move, fuse into each other, split; they can be born, develop, and die. Finally, we examine how some morphological features of holes are represented in perception, including the conditions whereby we have the impression that we see, feel, or even hear a hole. The book has over 150 pictures and is completed by a formal appendix, a section with puzzles and exercises, and a extensive annotated bibliography.

The methodological anarchy that characterizes much recent research in artificial intelligence and other cognitive sciences has brought into existence (sometimes resumed) a large variety of entities from a correspondingly large variety of (sometimes dubious) ontological categories. Recent work in spatial representation and reasoning is particularly indicative of this trend. Our aim in this paper is to suggest some ways of reconciling such a luxurious proliferation of entities with the sheer sobriety of good philosophy.

Quel bon vent, quel joli vent, ma vie m’appelle, ma vie m’attend French folk song 1. Presentists and Growing Block theorists appeal to ‘powerful intuitions’ when they defend their respective conceptions of time . Eternalists are prepared to go some length towards ‘reconciling’ the view from nowhen with at least some of these intuitions, or try to explain them away . Unaided intuitions may in fact underdetermine any particular metaphysical choice. One set of intuitions about time seems to have been neglected, though, in spite of its power. These intuitions are the mirror image of those supporting the Growing Block theory , and they are modelled on a pre-reflective understanding of our own life. According to the intuitions, only the future and the present are real; the past isn’t. The present is the constantly eroding edge of the future, which thus shrinks incessantly. There is less and less future as the present proceeds. The obvious intuitive model of this view of time is our life; from which every day eats up a little bit. Smaller scale models are available in everyday life. As you are reading this text, you have less and less to read. You know it. You know that at some point you’ll finish, or stop, reading it. But a model is not enough to make a grand philosophical claim, and indeed the very existence of the model is the ground for a negative claim: a picture, it may be said, is holding you captive. The Future Shrinker has two tasks. The first is to show that the intuitive picture supporting the claim is robust and does not make implausible epistemological claims. The second task is to show that her theory is at least compatible with scientific lore, and at best a good way ….

Thinking about space is thinking about spatial things. The table is on the carpet; hence the carpet is under the table. The vase is in the box; hence the box is not in the vase. But what does it mean for an object to be somewhere? How are objects tied to the space they occupy? This book is concerned with these and other fundamental issues in the philosophy of spatial representation. Our starting point is an analysis of the interplay between mereology (the study of part/whole relations), topology (the study of spatial continuity and compactness), and the theory of spatial location proper. This leads to a unified framework for spatial representation understood quite broadly as a theory of the representation of spatial entities. The framework is then tested against some classical metaphysical questions such as: Are parts essential to their wholes? Is spatial colocation a sufficient criterion of identity? What (if anything) distinguishes material objects from events and other spatial entities? The concluding chapters deal with applications to topics as diverse as the logical analysis of movement and the semantics of maps.

Descriptive metaphysics investigates our naïve ontology as this is articulated in the content of our perception or of our pre-reflective thought about the world. But is access to such content reliable? Sceptics about the standard modes of access (introspection, or language-driven intuitions) may think that investigations in descriptive metaphysics can be aided by the controlled findings of cognitive science. Cognitive scientists have studied a promising range of representational advantages, that is, ways in which cognition favours one type of entity over another. The notion of representational advantage is investigated and some scepticism is expressed as to its appropriateness for use in descriptive metaphysics

The relationships between art and cognition constitute a very wide set of largely unexplored and at times undefined or much too speculative problems. The field is narrowed down by imposing some constraints. It is proposed that the depiction of cast shadows, in its early history, could provide an ideal case study which conforms to the constraints. This paper addresses some methodological problems of the study of this case. A sample of relevant Renaissance images is discussed. A typology of depicted cast shadows is proposed upon which further empirical research could be built