Scientific observers often view living systems as existing in spaces which they conceptualize or abstract from the phenomena with which they deal. Ex… - James Grier Miller

The structure of a system is the arrangement of its subsystems and components in three-dimensional space at a given moment of time. This always changes over time. It may remain relatively fixed for a long period or it may change from moment to moment, depending upon the characteristics of the process in the system. This process halted at any given moment, as when motion is frozen by a high-speed photograph, reveals the three-dimensional spatial arrangement of the system's components as of that instant.

In 1978 when the book Living Systems was published, it contained the prediction that the sciences that were concerned with biological and social sciences would, in the future, be stated as rigorously as the “hard sciences” that study such nonliving phenomenon 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...
It is our opinion that this book represents an important step in the development of a quantitative living systems science... As Simms shows, the concepts of available energy and the capacity to direct energy, as well as the causative relationship between information and behavior, are useful in the analysis of behavior... The systems with which this first book of the series is concerned are mainly at the level of the cell and the animal organ and organism.... It will be interesting to see how the science is applied in later volumes to the complex behaviors of human being, and higher level systems.

# A space of frequency of intermarriage among ethnic groups.