E. J. Lowe

(1950 - 2014)

Recently, Terry Horgan and Matjaž Potrč have defended the thesis of ‘existence monism’, according to which the whole cosmos is the only concrete object. Their arguments appeal largely to considerations concerning vagueness. Crucially, they claim that ontological vagueness is impossible, and one key assumption in their defence of this claim is that vagueness always involves ‘sorites-susceptibility’. I aim to challenge both the claim and this assumption. As a consequence, I seek to undermine their defence of existence monism and support a common-sense pluralist ontology of ‘ordinary objects’ as being fully consistent with a thoroughgoing metaphysical realism.

Three different concepts of matter are identified: matter as what a thing is immediately made of, matter as stuff of a certain kind, and matter in the (dubious) sense of material ‘substratum’. The doctrine of hylomorphism, which regards every individual concrete thing as being ‘combination’ of matter and form, is challenged. Instead it is urged that we do well to identify an individual concrete thing with its own particular ‘substantial form’. The notions of form and matter, far from being correlative, are relatively independent. There is nothing absurd in the notion of form without matter. Matter provides neither a principle of individuation nor a criterion of identity for individual concrete things: their form alone provides both. Finally, a substance ontology which admits also the existence of particular qualities, or tropes, is to be preferred both to a substance ontology which denies the existence of tropes and to a pure trope ontology.

There is currently intense interest in the question of the source of our presumed knowledge of truths concerning what is, or is not, metaphysically possible or necessary. Some philosophers locate this source in our capacities to conceive or imagine various actual or non-actual states of affairs, but this approach is open to certain familiar and seemingly powerful objections. A different and ostensibly more promising approach has been developed by Timothy Williamson, according to which our capacity for modal knowledge is just an extension, or by-product, of our general capacity to acquire knowledge of true counterfactual conditionals — a capacity that we deploy ubiquitously in everyday life. Williamson’s account crucially involves a thesis to the effect that modal truths can be explained in terms of counterfactual truths. In this paper, I query Williamson’s account on a number of points, including this thesis. My positive proposal, which owes a debt to the work of Kit Fine on modality and essence, appeals instead to our capacity to grasp essences, understood in a neo-Aristotelian fashion, according to which essences are expressed by ‘real definitions’.

Objects which philosophers have traditionally categorized as abstract are standardly referred to by complex noun phrases of certain canonical forms, such as ‘the set of Fs’, ‘the number of Fs’, ‘the proposition that P’, and ‘the property of being F’. It is no accident that such noun phrases are well-suited to appear in ‘Fregean’ identity-criteria, or ‘abstraction’ principles, for which Frege’s criterion of identity for cardinal numbers provides the paradigm. Notoriously, such principlesare apt to create paradoxes, and the most intuitively plausible ‘Fregean’ identity-criterion for properties is afflicted by this problem. In this case, it may be possible to overcome the difficulty by modifying the criterion in a way which requires an independent account of the existence-conditions of properties, but it appears that such a strategy demands acceptance of the doctrine of immanent realism—the view that a property exists only if it is exemplified by some object.

I propose a fourfold categorisation of entities according to whether or not they possess determinate identity-conditions and whether or not they are determinately countable. Some entities – which I call ‘individual objects’ – have both determinate identity and determinate countability: for example, persons and animals. In the case of entities of a kind K belonging to this category, we are in principle always entitled to expect there to be determinate answers to such questions as ‘Is x the same K as y?’ and ’How many Ks are there satisfying condition C?’, even if we may sometimes be unable in practice to discover what these answers are. But other entities apparently lack either determinate identity, or determinate countability, or both. In these terms I try to explain certain important ontological differences between familiar macroscopic objects and various rather more esoteric entities, such as the ‘particles’ of quantum physics, quantities of material stuff, and tropes or property instances.

In this paper, I first of all define various kinds of ontological dependence, motivating these definitions by appeal to examples. My contention is that whenever we need, in metaphysics, to appeal to some notion of existential or identity-dependence, one or other of these definitions will serve our needs adequately, which one depending on the case in hand. Then I respond to some objections to one of these proposed definitions in particular, namely, my definition of (what I call) essential identity-dependence. Finally, I show how a similar approach can be applied in the theory of truthmaking, by offering an account of the truthmaking relation which defines it in terms of a type of essential dependence. I also say why I think that this approach is preferable to one which treats the truthmaking relation as primitive. More generally, my view is that accounts of dependence or ‘grounding’ which treat these notions as primitive are less satisfactory than my own position, which is that in all cases a suitable definition is forthcoming if we look hard enough.