What does reality encompass? Is reality exclusively physical? Or does reality include nonphysical -mental, and perhaps 'abstract' -aspects? What is it to be physical or mental, or to be an abstract entity? What are the elements of being, reality's raw materials? How is the manifest image we inherit from our culture and refine in the special sciences related to the scientific image as we have it in fundamental physics? Can physics be understood as providing a 'theory of everything', or do the various sciences make up a hierarchy corresponding to autonomous levels of reality? Is our conscious human perspective on the universe in the universe or at its limits? What, if anything, makes ordinary truths, truths of the special sciences, and truths of mathematics true? And what is it for an assertion or judgment to be 'made true'?
In The Universe As We Find It, John Heil offers answers to these questions framed in terms of a comprehensive ontology of substances and properties inspired by Descartes, Locke, their successors, and their latter day exemplars. Substances are simple, lacking parts that are themselves substances. Properties are modes -particular ways particular substances are -and arrangements of propertied substances serve as truthmakers for all the truths that have truthmakers. Heil argues that the deep story about the nature of these truthmakers can only be told by fundamental physics.