E. J. Lowe

(1950 - 2014)

John Heil’s new book is remarkable in many ways. In a concise, lucid and accessible manner, it develops a complete system of ontology with many strikingly original features and then applies that ontology to fundamental issues in the philosophy of mind, with illuminating results. Although Heil acknowledges his intellectual debts to C. B. Martin, he is unduly modest about his own contribution to the development and application of this novel metaphysical system. A full examination of the position that Heil defends would require a book in itself, so I shall limit myself to discussing some of its central themes and to explaining a few doubts that I have concerning some aspects of it.

Commonsense metaphysics populates the world with an enormous variety of macroscopic objects, conceived as being capable of persisting through time and undergoing various changes in their properties and relations to one another. Many of these objects fall under J. L. Austin’s memorable description, “moderate-sized specimens of dry goods.” More broadly, they include, for instance, all of those old favourites of philosophers too idle to think of more interesting examples—tables, books, rocks, apples, cats, and statues. Some of them are natural objects, such as rocks, apples, and cats. Some are artefacts, such as tables, books, and statues. Some are living things, such as apples and cats. Some are inanimate things, such as tables, books, rocks, and statues. To such a list we could add much larger natural objects, such as planets and stars, as well as much smaller ones barely visible to the naked eye, such as mites and pollen grains. Telescopes and microscopes enable us to extend the scale further in both directions, to include such things as galaxies and microbes. To call into question the existence of all or any of these things would appear to be an extravagance of the sort that only a philosopher could indulge. Until fairly recently in the history of philosophy, however, the only way in which their existence would have been called into question was in the context of the debate between realism and idealism. Idealism calls their existence into question by questioning the existence of an “external world” as such, proposing instead that only minds and their experiences exist. What is much more recent is the suggestion that, although there is an external world of entities existing in space and time, it is not in fact populated by most, or perhaps even by any, of the objects recognized by common sense. Instead, it is suggested, the world is populated by submicroscopic entities of a highly esoteric kind best understood by theoretical physicists—entities which may not even qualify as “objects” in anything like the familiar sense because, quite possibly, they should not be thought of as having precise spatiotemporal locations or as persisting over time and through processes of qualitative change. Let us call these putative entities ‘atoms’, without prejudice as to whether they conform to the descriptions currently favoured by physicists in speaking of what they call ‘atoms’. In other words, let us use ‘atom’ as a place-holder for whatever kind or kinds of entities an ideal or completed physics would postulate as the “ultimate” constituents, as opposed to infinitely descending levels of ever more fine-grained physical structure, but let us set aside dispute over these alternatives for the time being, if only because we have little idea as to how to settle it.

Following the lead of Gustav Bergmann ( 1967 ), if not his precise terminology, ontologies are sometimes divided into those that are ‘relational’ and those that are ‘constituent’ (Wolterstorff 1970 ). Substance ontologies in the Aristotelian tradition are commonly thought of as being constituent ontologies, because they typically espouse the hylemorphic dualism of Aristotle ’s Metaphysics – a doctrine according to which an individual substance is always a combination of matter and form. But an alternative approach drawing more on the fourfold ontological scheme of Aristotle’s Categories is not committed to this doctrine and may regard individual (or ‘primary’) substances as having no constituent structure, their only possible complexity residing in their possession, in some cases, of a multiplicity of substantial parts. However, as we shall see, this does not imply that such an ontology falls instead into the relational camp: for although it invokes, in addition to the category of individual substance, also those of substantial kind (‘secondary’ substance), attribute, and mode (or ‘individual accident’), it need not and arguably should not take there to be external relations between entities in the different categories. On this view, truths of exemplification and instantiation, such as ‘Dobbin is white’ and ‘Dobbin is a horse’, do not need relational truthmakers. Hence, it can be maintained that there are no such relations as ‘exemplification’ and ‘instantiation’, at most only certain relational truths of exemplification and instantiation – truths whose logical form is relational. Th is being so, I shall argue, such an ontology cannot fairly be classified as a ‘relational’ one.

I raise three questions concerning Locke's doctrine of substratum, in the light of his correspondence with Stillingfleet: (1) What was his doctrine?(2) Is it philosophically defensible?(3) Is it consistent with his empiricist epistemology? I defend answers which represent Locke's doctrine as being only partially successful but amenable to improvement in certain ways. C.B. Martin has proposed an alternative interpretation of Locke's position. I examine this and find it to be admirable in many respects but implausible in others.