Tending Adams Garden: Evolving the Cognitive Immune Self [Paperback]

In this book the author makes a seemingly radical hypothesis, namely that human immune system is in fact a cognitive system. Those who think of a cognitive system as also being one that is conscious will find the author's contention perhaps even more radical. However, the author's notion of a cognitive system is not as elaborate, and such systems are very prevalent in manufacturing and control systems, telecommunication networks, and military systems.

The book is targeted toward a wide readership, and therefore the author omits detailed scientific jargon and also omits many references. Readers (such as this reviewer) who are not experts in immunology though can still gain a lot of insight into the workings of the human immune system, and the book could be read as an introduction to this important field. In fact, a non-expert in immunology might gain much more from the book than an expert, for the former has not been biased by the "classical" clonal selection theory of the immune system, and will therefore be more open to the prospect of a different paradigm. The physicist/mathematician reader will find an interesting use by the author of chaotic dynamical systems and its notion of an attractor. The use of these concepts goes along with the author's notion of evolution and adaptation, which he describes as a radical departure from the standard view. Adaptation, in his view, is defined as an attractor, and is not correlated with improvement of the organism. Evolution does not involve the `improvement of DNA' but rather is the `creation and occupation of attractors.'

The main virtue of this book is the author's careful elucidation of the notion of a cognitive system. This is necessary in his view in order to distinguish such a system from one that might qualify as being cognitive, but one would not want to view as being cognitive. As evidence of the latter, he gives the example of the production of urine by the kidneys. Such a system he says exhibits complexity, precision, and regulation that rivals many nervous systems, but one that should not qualify as being cognitive. A cognitive system he argues is able to make decisions, is able to form images of their environments, and is able to learn from experience. This learning ability involves the updating of their internal structures and images, which the author refers to as `self-organization.' Hence `choice,' `internal images,' and `self-organization' allows the cognitive system, and therefore the organism that possesses it, to interact with the world that will give it distinct advantages over what can be obtained from evolutionary genetics.

So what is the nature of the `images' of the environment encoded by the immune system? They are merely proteins, some of which are distributed throughout the body and form geometrical shapes as well as `abstract, functional' ones. These images are also of two types, the `innate' images, which are inherited, and `acquired' images, which arise from the cognitive process. Autoimmune diseases, the author argues, involve an image dysfunction in the immune system.

A cognitive view of the immune system the author thinks is necessary because of the need for immune receptors to have the ability for specific recognition. However, they are degenerate, `pleiotropic', redundant, and random observes the author, and this means that cognition (as he defines it) is necessary in order that the immune system generate specificity out of the non-specificity of its components. The author outlines in detail how to construct immune cognition, this involving the `geometry' of cognition, the `dynamics' of cognition, and the `images' or `patterns' of cognition.

In terms of its ability to engage in cognitive decision-making, the immune system reacts to a pattern of signals that it receives by selecting a particular type of response pattern from its collection of available responses. An `immune language' that combines germ-line and somatic `chemical words' is used to make the decisions. These choices, the author emphasizes, are not the result of any `self-reflective consciousness' or `mystical free will' but in fact are deterministic. Choices in the immune system can occur because it can exercise options and because it can learn. From a chemical perspective, the decision-making in the immune system involves associating somatic perceptions of objects with classes of effector responses in the germ-line.

These views of immune system decision-making are fascinating, and will certainly invoke strong reactions from the philosophical community. Indeed, what is normally thought of as capabilities only found in a `mind,' namely that of abstraction, semantics, and context, these can also be found in the human immune system. It communicates via molecular interactions; its antigens and cytokines express semantic attributes since they can confirm ligands and their receptors and can arrange the signal molecules in patterns; and can patterns of signals can create a signal context.

The immune system can be defective, this resulting among other things in the deadly autoimmune diseases. The author discusses this unfortunate circumstance in detail in the book, but he is also willing to contemplate deliberate intervention into the workings of the immune system in order to circumvent any problems with it. In the last paragraph of the book, noting that "two cognitive systems are better than one," the author advocates the deliberate engineering of the immune system, i.e. that of turning "on or off the immune response as we see fit." Along with genetic engineering, metabolic engineering, and other endeavors of twenty-first century technology, such a prospect is awesome.

Cohen's book is the first book I've read about immunology that baldly goes where no book has gone before. Cohen does not seem to be afraid to explore the field of immunology with what used to be the holdings of other fields. He doesn't hesitate to use philosophy, computer science and physics whenever the need arises. He not only ignores the superficial boundaries between the fields we were brought up on, but he even presents immunology in a way that seems obvious, given the other sciences of the 20th century. It is evident from the book that Cohen has a clear agenda and his own theory on the structure of the immune system. What many immunologists try so much to ignore - the urgent need for a new theory replacing the 50-year-old Clonal Selection Theory, turnes in his hands from a problem to a solution. Anyone interested in seeing how science is about to change, how borders between disciplines disappear and how immunology can be the basis to learning information theory, network theory, philosophy, system design, biology, evolution, cognitive systems and much more. And do all that while getting to know one of the most ingenious systems - the immune system, should read the book.

I.R. Cohen has written an intelligent, witty, deep, thought provoking, iconoclastic exploration of "inner-space" A must for the layman and student who want to understand the immune system and for scientists who can learn how to write and explain complex material with humor, grace and respect for the reader. Keep goin Cohen!