on 5 May 2013
Ontology, roughly, is the study of what exists and what these things are like. At first sight, this might sound like an odd and otherworldly field of study, but simple examples make clear that ontology touches upon some very natural everyday questions, such as: Do numbers exist? If yes, what does that even mean? Do works of music exist? As works of music are generally not placed at some particular point in time and space, the answer to this question is not obvious either: A work of music is somehow an abstract, not concrete, entity. Thus, ontology is not as disconnected from the real world as it might seem at first glance.
In "An introduction to ontology", Effingham discusses a series of classical problems of ontology: The existential status of for example properties, numbers, space, time and physical objects and their constituents. The book is well structured, and contains chapters with intertwined discussions of concrete problems as well as general methods used for their resolution. This is a format which works very well: It manages to give an overview of some broad approaches to ontology while at the same time demonstrating how these approaches can be used to shed light on concrete ontological questions. Furthermore, the book is overall reasonably non-technical, explaining jargon as it comes around. The book does require some familiarity with first-order logic, that is, quantifiers such as "for all" and "there exists", logical connectives such as "and" and "or", et cetera. Not much is required, though, if you consider yourself capable of abstract logical thinking at a reasonable level, this probably will not be an issue.
The book can be somewhat frustrating reading, but this is not necessarily by fault of the author. Many different approaches to ontology are presented, and Effingham generally gives them all a fair chance, which is great. As a reader, however, you will no doubt find that some of the ideas presented will strike you as somewhere between ridiculous and downright stupid. I don't think it to be fair, however, to criticize the book for this, rather it is a strength that the book gives an overview of many different competing theories.
I do think that the book can reasonably be criticized for not sufficiently discussing what we actually mean by saying that something exists. The chapter on methodology does cover a good deal of ground here, but it appears to me that later chapters often would have benefited by taking more of a birds-eye view and asking questions such as: What do we actually want the verb "to exist" to mean? Do some things exist in a different sense than other things, or is existence sort of an either-or property? If it is not completely clear what is meant by the claim that a particular thing exists, discussions easily get unnecessarily muddled.
Overall, however, this is an accessible and well done introduction to an interesting subject, and can easily be recommended for anyone with an interest in the topic.