With ontology motivated largely by causal considerations, this lucid and provocative work focuses on the idea that physical objects are causally non-redundant. Merricks "eliminates" inanimate composite macrophysical objects on the grounds that they would--if they existed--be at best completely causally redundant. He defends human existence by arguing, from certain facts about mental causation, that we cause things that are not determined by our proper parts. He also provides insight into a variety of philosophical puzzles, while addressing many significant issues like free will, the "reduction" of a composite object to its parts, and the ways in which identity over time can "for practical purposes" be a matter of convention. Anyone working in metaphysics will enjoy this book immensely.
I read this after van Inwagen's Material Beings. In large part, Merricks's book is derivative of van Inwagen's work. The one original idea of significance it contains, the argument from causal redundancy, merited an article, not an entire book.
I want to give Merricks the standard quota of respect, but given the annoyingly numerous derisive jabs at "the folk," and the intervening twenty years, I'll come out and say it: Merricks comes across as a van Inwagen wannabe, sharing an implausible number of strangely conjoined beliefs with the more venerable Father Peter: Christian belief, physicalism, libertarianism about free will, disbelief in middle-sized non-animal objects . . . I'm sure they have even more -isms in common, but you get the point.
Although there is a great deal of careful reasoning devoted to micro-points in this work, regarding more important lines of argument Merricks gets rather lazy. He fails, for example, to consider the strongest opposing position (the intuitive one taken up by Amie Thomasson in Ordinary Objects. The assumption of libertarian free will conjoined with physicalism places severe restrictions on the number of philosophers likely to be sympathetic.
Merricks' conclusion is this: There are no chairs, tables, stars, statues. Though you might initially find this idea absurd Merricks' arguments render the idea at least reasonable, if not plausible.
His arguments include proofs that try to show directly that ordinary objects should be eliminated for our ontology as well as examples that show how the eliminativist thesis is useful to solving other philosophical problems.
Overall, Merricks writing is extremely readable, his arguments are novel and interesting, and I recommend this book to anyone interested in ontology of ordinary objects.