Roush+Book+Review

//The Logic of Life: A History of Heredity// by Francois Jacob

François Jacob’s //The Logic of Life// is a history of the views of science toward heredity. The book’s sequence in discussing this history is very logical, taking each view of heredity in chronological order and discussing how it was that scientists came to determine that this view was incorrect. Jacob seems to have chosen heredity as a case study of how science changes because, apart from being a molecular biologist himself and wanting to draft a history of his field, Jacob saw three deeply important features of the study of heredity. Heredity is one of the oldest questions pondered by humanity, while at the same time being the one of the most difficult questions to unravel. Furthermore, what scientists have unraveled about heredity has had some of the deepest philosophical impacts on humanity of any scientific endeavor. Each debate in the field of heredity that Jacob discusses is viewed in light of those three characteristics; how long ago the debate was, what difficulty was surpassed in order to allow evidence to suggest the new theories, and what the social and philosophical implications of the new theories were. Jacob’s book deals greatly with a major topic of biology called emergent properties. The concept of emergent properties is the idea of a system having properties that are not present among any of the constituents of the system. Jacob makes the indirect argument, indirect because he never actually uses the term “emergent properties,” that this idea is behind the debunking of every major theory of heredity since the 17th century. The book is organized in the sequence of chronology starting in the 1600s when heredity and the creation of a new human through reproduction was seen as being too miraculous and complex to be governed by the known laws of physics, and therefore it was thought that the creation of a new life through reproduction was purely a direct act of God. However, increasing knowledge of physics and chemistry, and later biology, explained how reproduction and life in general are not direct acts of God, but rather they are predictable consequences of the known laws of physics and chemistry. This is all, of course, explained through the history of heredity, but picking to discuss such a specific topic made the story all the more interesting. The scientific evolution from the times of believing that all people and animals were preformed at the time of Creation and waited within the bodies of their ancestors for the time of their eventual birth up to the modern theory of heredity which is based on DNA and the random joining of a haploid sperm and egg makes for an interesting story of one of the areas of science in which scientists have cleared the most dust from their eyes, while still having so many more questions to answer. While Jacob has created what seems to be a very complete history of the study of heredity, this history was at many points difficult to follow given the way Jacob related. He frequently referred to scientists solely by their last name, and without explaining who they were. Also, many of the names mentioned in the book are mentioned only once while a few others become large talking points. This presented a problem because I began to get lost in the thick stew of names to the point where I couldn’t focus on the ideas behind the names. When I did stop focusing on the names, I was also missing out on the important names which would later become key modes for relating the history of heredity, thus making me confused as I continued into the story of the history of heredity. Most of this consequence of using many names comes from the fact that I just did not know who the people were, and I come to this conclusion because when I saw names that I did know I was not nearly as lost. However, if every person introduced was explained in some way which gave them some distinction from every other faceless name in the book, then I might never have gotten lost while reading the book, and it would have been a much more compelling read for me. The main reason why I chose to read //The Logic of Life// was that I am a Biochemistry and Biophysics major and I wanted to learn about the history of what eventually became molecular biology. Specifically, I wanted to learn the specifics of the modern theories of heredity and how they came to be. This topic, however, was only discussed, and only very generally, in the last quarter of the book. Looking back at the beginning of the book, I noticed that the second sentence is: “This book is a history of the questions raised about heredity rather than of the answers provided.” This statement succinctly explains why I was at first disappointed with regard to this book. However, re-reading that sentence gave me a better appreciation for the book. In a literal sense, the book is exactly as it is subtitled; “A History of Heredity.” In a more real and important sense, the book is a history of the development of the idea of emergent properties. In light of this revelation about the meaning of the book, I re-read some sections of the book. Even when I took them out of context as I did, the sections made perfect sense as a story of the development of the idea of emergent properties. The idea of this being the point of the book especially makes sense in regard to the final section of the book entitled, “The Integron.” In this section, he discusses the idea that “at each level, units of relatively well defined size and almost identical structure associate to form a unit of the level above. Each of these units formed by the integration of sub-units may be given the general name ‘integron.’ An integron is formed by assembling integrons of the level below it; it takes part in the construction of the integron of the level above.” In the end, Jacob sums up the whole story of heredity as being the chief case-study which proved the importance of the idea of integrons. It is a desire to relate the importance of integrons, not a desire to relate the history of heredity, which prompted Jacob to write this book. In light of this idea, I find the book extremely compelling and see it as being important not just in relation to biology, but in relation to all of the sciences.