What the heck is "complexity" anyway? This is one of the questions Mitchell tries to answer in this wide ranging introduction to emergent phenomenon.
In Complexity, A Guided Tour Mitchell embarks on a highly readable and wide ranging overview of the world of complexity. From the beginning, one might reasonably ask, "What does it mean to speak of the complexity of something?" Good question.
What is Complexity?
Complexity seems to have as many definitions as there are people willing to take a shot at defining it. Is it a measure of how hard something is to understand? Are complex things harder to explain than simple things? Are complex systems self-organizing without the benefit of an obvious central controller? Do they evolve? Does complexity result in emergent properties that are somehow greater than a simple sum of parts? Apparently the answer to all these questions is--yes.
As examples of complex systems, which are then discussed in greater detail later in the book, Mitchell offers insect colonies, the human brain, the immune system, economies, the world wide web, and a few other entities.
What exactly makes these systems complex? Mitchell offers up some ideas on the things that all "complex" systems have in common, and provides the thoughts of a number of other luminaries in the field as well. To her credit, Mitchell even discusses that fact that some people think the entire field of complexity theory is a bogus waste of time. Time will tell.
"The best popular science books are those that give the reader the sense of looking over the shoulder of a leading researcher doing cutting-edge work at the frontier of scientific inquiry. Walter Isaacson's recent biography of Einstein belongs in this category. So too does Melanie Mitchell's 'Complexity: A Guided Tour,' a comprehensive new book chronicling the latest advances in the sciences of complexity." - James Gardner, The Oregonian
"How can something be dependent and autonomous at the same time? And why do so many systems in nature show this hierarchical organization? No one has answered these questions, but in Complexity, computer scientist Melanie Mitchell of the Santa Fe Institute, New Mexico, offers a valuable snapshot of the growing field of complex-systems science from which the answers may eventually arise." - Mark Buchanan, Nature
Melanie Mitchell is Professor of Computer Science at Portland State University, and External Professor and Member of the Science Board at the Santa Fe Institute. She attended Brown University, where she majored in mathematics and did research in astronomy, and the University of Michigan, where she received a Ph.D. in computer science, Her dissertation, in collaboration with her advisor Douglas Hofstadter, was the development of Copycat, a computer program that makes analogies. She has held faculty or professional positions at the University of Michigan, the Santa Fe Institute, Los Alamos National Laboratory, the OGI School of Science and Engineering, and Portland State University. She is the author or editor of five books and over 70 scholarly papers in the fields of artificial intelligence, cognitive science, and complex systems. Her most recent book, Complexity: A Guided Tour, published in 2009 by Oxford University Press, is the winner of the 2010 Phi Beta Kappa Science Book Award. It was also named by Amazon.com as one of the ten best science books of 2009, and was longlisted for the Royal Society's 2010 book prize.