This is a serious and important book dealing with the concepts that underpin models of explanation, the nature of psychiatric phenomena, and whether psychiatric taxonomy reflects ‘real’ diseases. It grew out of a conference held in Copenhagen in 2006.

If anything, this book confirms that psychiatry is a complex subject. Sandra Mitchell deals with this by describing the general features of complexity and distinguishing between compositional and dynamic complexity. Her case is that complexity has implications for our explanatory theories and that in psychiatry in particular reductionist methods that attempt to decompose complexity to its constituent parts are unlikely to be successful.

The chapter by James Woodward, ‘Cause and explanation in psychiatry’, is perhaps the most illuminating. Woodward asks what on the face of it is a simple question: to what extent do candidate causal explanations involving ‘upper-level’ or relatively coarse-grained or macroscopic variables such as mental or psychological states (e.g. highly self-critical beliefs or low self-esteem) or environmental factors (e.g. parental abuse) compete with explanations that instead appeal to underlying, ‘lower-level’ or more fine-grained neural, genetic or biochemical mechanisms? In order to answer this question Woodward makes clear that causal relationships are different from correlational relationships. He defines a cause as something that ‘must make a difference to its effect… there must be at least two possible states, corresponding to the cause being present or to the cause being absent or to the cause being in one state rather than in another such that which of these is realised is associated with some change or difference in the state of the effect (p. 143)’. Here Woodward is stating the obvious but often the obvious bears repeating. Furthermore, he develops a model for judging the quality of an explanation of causal claim.

The section on phenomenology is testing for the reader in that it draws on Continental philosophical tradition – the technical language and the concepts that underpin this section are somewhat less familiar to the reader from the English-speaking world. Phenomenology is interested in the mental contents and observable behaviours of psychiatric patients as well as what these reveal about ‘the basic constitutive structures of consciousness such as self-awareness, embodiment, spatiality, temporality, and intersubjectivity’.

Shaun Gallagher clarifies the distinction between intentional actions and mere movement. These two terms are often conflated and this conflation is the basis of the confusion in the literature between the neural underpinning of intentions and what is termed the illusion of conscious will.

Josef Parnas in the epilogue writes: ‘Our goal in this book has been to expose you to first rate philosophical thought addressing a range of issues central to the science and practice of psychiatry. Philosophy is not like natural sciences in striving for a definitive solution of an issue – of proposing the answer. Rather the goal has been to stimulate the readers to think more clearly and more deeply about the problems before you (p. 395)’. The authors have definitely challenged the reader to reflect on the complexity of psychiatry. Some of the ideas are tough and not easy to grasp. If anything, the complexity of the biology of psychiatric disorders is matched by the complexity of the potential causal explanations. This is not a book for everyone but it is certainly one that researchers, scholars and anyone involved in trying to explain the nature of psychiatric disorders to a sceptical audience ought to read.