Anthony Quinton's The Nature of Things covers competently a good deal of philosophical ground in hopeful pursuit of a coherent ontology de-scribable as ‘a version of materialism’. He seems to discern two major difficulties for the enterprise: first, that of giving an acceptable account of ontology, and, secondly, that of reconciling his naturalism with his empiricist principles. ‘Naturalism’ is the view that man and his doings constitute a part of nature on the same ontological level as other natural things, and materialism is a naturalist philosophy. Of the second difficulty Quinton writes:

…a naturalistic view of the world has had to find its chief philosophical expression through doctrines of a sceptical and subjectivist kind, such as Hume's, which have a tendency to undermine the naturalistic presumptions which inspired them. In this book I have tried to equip materialism with solid philosophical credentials.