J. T. M. Miller 
Metaphysical Realism and Anti-Realism [PDF ebook] 

Minimally, metaphysical realists hold that there exist some mind-independent entities. Metaphysical realists also (tend to) hold that we can speak meaningfully or truthfully about mind-independent entities. Those who reject metaphysical realism deny one or more of these commitments. This Element aims to introduce the reader to the core commitments of metaphysical realism and to illustrate how these commitments have changed over time by surveying some of the main families of views that realism has been contrasted with: such as (radical) scepticism, idealism, and anti-realism.