Abstract

Many of the concepts analysed by philosophers have their origin in ordinary – or at least extra-philosophical – language. Perception, knowledge, causation, and mind are examples. But the concept of substance is a philosophical term of art. Its uses in ordinary language tend to derive, often in a rather distorted way, from the philosophical senses. There is an ordinary concept in play when philosophers discuss “substance”, and this, as we shall see, is the concept of object, or thing when this is contrasted with properties or events. But such “individual substances” are never termed “substances” outside philosophy. There exist two rather different ways of characterising the philosophical concept of substance. The first is the more generic. The philosophical term “substance” comes from an early Latin translation of the Greek ousia. Ousia is a noun derived from the verb “einai” (to be) and is naturally translated “being”. According to the generic sense, substances are those things that best merit the title “beings”. This is usually interpreted to mean those things that are the foundational or fundamental entities of a given philosophical system. Thus, for an atomist, atoms are the substances, for they are the basic things from which everything is constructed. In David Hume’s system, impressions and ideas are the substances, for the same reason. In a slightly different way, Forms are Plato’s substances, for everything derives its existence from Forms. The second use of the concept is more specific. According to this usage, substances are a particular kind of entity, and some philosophical theories acknowledge them and others do not. This conception of substance derives from the intuitive notion of individual thing or object, which contrasts mainly with properties and events. According to this usage, it is a live issue whether the fundamental entities are substances or something else, such as events, or properties located at space-times. The issue is how we are to understand the notion of an object, and whether, in the light of the correct understanding, it remains a basic notion, or one that must be characterised in more fundamental terms. Whether, for example, an object can be thought of as nothing more than a bundle of properties, or a series of events. The reason “substance” has acquired these two usages is that the work that introduced the term to philosophy, Aristotle’s Categories, claims that the things that most merit the title “beings” (substances in the generic sense) are individual objects as opposed to properties or events (substances in the specific sense).