In 1978, when the book Living Systems was published, it contained the prediction that the sciences that were concerned with the biological and social sciences would, in the future, be stated as rigorously as the "hard sciences" that study such nonliving phenomena as temperature, distance, and the interaction of chemical elements. Principles of Quantitative Living Systems Science, the first of a planned series of three books, begins an attempt to fulfill that prediction. The view that living things are similar to other parts of the physical world, differing only in their complexity, was...