Kenneth Schaffner’s Behaving:  What’s Genetic, What’s Not, and Why Should We Care? is a thorough, in-depth discussion of contemporary scientific inquiry into behavior and the philosophical implications of recent discoveries in the field.

          After a short preface and introduction, the book is divided into nine chapters.  The first two chapters provide a clear and engaging introduction to key terminological distinctions used throughout the book.  The next three chapters use analytic philosophy to analyze the problems of associating behavior with genetics, using the genetics of worms as a model to demonstrate the complexity and difficulty of drawing this connection.  The next three chapters focus on human genetics, with chapter 6 focusing on personality genetics, chapter 7 on schizophrenia, and chapter 8 discussing an apparent threat genetics poses to (libertarian) free will.  In chapter 9 – the final chapter – Schaffner sums up the main themes of the book, arguing that the accomplishments of contemporary genetics are modest, but that there is reason to be optimistic about future discovery.

          In chapters 1 and 2, Schaffner provides a necessary, and suitably thorough introduction to key terms in the field of “behavioral genetics”, taking care to distinguish these terms from colloquial definitions.  Notably behavior is defined as a broad term including reactions and interactions, and genetics is defined as the science dealing with inheritance of characteristics passed on by parents, seemingly excluding other sources of changes to genes (including mutation and various means of editing/changing genetic material, such as genetic engineering).  These chapters include three engaging dialogues that help to clarify subtle distinctions, as well as a bevy of illustrations and charts to further illustrate key ideas. 

          The following chapters include clear, concise analysis, and are clear to spell out various pitfalls and dispel preconceived notions that can trouble novice and expert alike.  In chapter 3, he lists what he calls “Seven Deadly Sins of Causation” including the nature-versus-nurture dichotomy (contending that there is wide consensus that both nature and nurture play important roles in determining development and behavior) and the one-gene-causes-one-behavior fallacy (the overly simple theory that a single gene is responsible for a single behavior).  The author uses the example of a common worm – a somewhat simple organism compared to human beings – to illustrate how many of these overly simplified beliefs go awry throughout chapters 3-5. 

Chapter 6 discusses at length the problems facing genetic and psychological accounts of behavior, including conflicting theories of personality.  Here he discusses the replication problem facing many contemporary scientists that threatens to undermine many of the conclusions that scientists have made regarding linking behavior and genetics.  Chapter 7 uses the study of schizophrenia genetics as a model for contemporary genetic investigation in humans.

Despite the thoroughness of the previous chapters, Chapter 8 – concerned with whether free will is compatible with determinism – is largely incomplete, and comes in at half the length of previous chapters.  He argues that many compatibilist accounts of free will, such as the view proposed by Harry Frankfurt, are compatible with genetic determinism.  For Frankfurt, an agent A has free will if and only if:

1)    A has the first-order desire to do x.

2)    A is causally determined by A‘s first-order desire to do x to act in such a way that A believes will bring about x.

3)    A has the second-order desire to be the sort of person who has the first-order desire to do x.

Schaffner discusses the well-known examples of the willing and unwilling drug addict here.  An unwilling drug addict has the first-order desite to do drugs, is causally determined by his desire to pursue drugs, but doesn’t want to be a drug addict (he has the second-order desire to be the sort of person without the first-order desire to do drugs).  The unwilling drug addict lacks free will for Frankfurt, but a willing drug addict is a different story.  The willing drug addict has a first-order desire to do drugs, is causally determined by this desire to drugs, and has a second-order desire to be the sort of person who has the first-order desire to do drugs – he desires to be a drug addict.  The willing drug addict possesses free will for Frankfurt.  But what about the drug addict whose second-order desire to be a drug-addict is caused by the drug?

          Schaffner contends that incompatibilist, libertarian free will, like that of leeway incompatibilist Robert Kane, is incompatible with what we “know” about contemporary science.  On Kane’s view, an agent A has free will if and only if:

1)    There exists a time t-n, such that at t-n, there are two or more possible futures, one in which at time t, A acts on her desire to x and one in which at time t, A acts on her desire not to x.

2)    There is some indeterministic event – a self-forming-act at some time between t-n and t, such that after this point, A comes to reflect upon their undetermined action and form desires that will causally determine A to act to do either x or not x.

Unfortunately, by “knowledge” here Schaffner seems to mean the basic, metaphysical assumption of determinism assumed for the scientific method.  However, this neglects the fact that many scientists work with a probabilistic account of causation, and others whose experimental data purports to undermoine the assumption of determinism with apparently indeterministic results – either of which would leave room for Kane’s self-forming-actions, or for alternative libertarian accounts, such as Derk Pereboom’s source incompatibilist view.

          Conclusion:  Chapters 1-7 in this book are well written, well organized, and well researched, and provide an excellent introduction to the science concerning genetics and what the discipline can reasonably show.  Chapter 8 is a surprising departure from previous chapters, explaining very little and neglecting the majority of contemporary and historic discussion concerning free will.  It is an underwhelming, and largely forced, conclusion to an otherwise exceptional work in philosophy of science.

 

© 2016 William Simkulet

 

William Simkulet, Ph.D., University of Wisonsin, Marshfield/Wood County