approach than believing it was swayed by humors, vapors, and evil spirits. Anchored in concreteness, from the seventeenth century onward, medical knowledge advanced in great strides. With the discovery of microorganisms, the picture seemed complete: The body was a machine, run by certain inner energy, which could break down due either to external agents( toxic substances or microorganisms) or to unexplained internal malfunctions. But the physical sciences have advanced far beyond the simple mechanics of the sixteenth and seventeenth centuries. Most of medicine, on the other hand, is still stuck in the old concept of the body as a system of pumps and pulleys, pipes and fluids. When a link is discovered between two events heretofore viewed as unrelated( food and mood, for example), the cry of the scientific community is,“ But what is the mechanism?” Although the alliance of medicine with Newtonian physics has given us a broad understanding of how we function, it is no longer sufficient to give us all the answers we need. Not everything can be explained in mechanistic terms( for example, why are certain foods related with certain moods in some people and not in others?). For this reason, increasing numbers of people are rejecting mechanistic medicine as they embrace a still broader, more holistic vision. Modern physics, always on the forefront, offers several elementary concepts to support that vision; we can apply these toward building a more satisfactory model of how our bodies really work. Thanks to precise and powerful aids to perception, such as the electron microscope and particle accelerators, physicists are finding out what mystics always knew: that the universe is more than the sum of its parts, 2 and that reality is a complex web of relationships. Analyzing its parts is not enough to grasp it. To help us understand it better, a new approach has evolved: systems theory. According to Fritjof Capra, it is an effort to describe wholes in terms of the relationships between their parts rather than in terms of the parts themselves, 3 and living systems are described as patterns of organization. Systems theory is supported by systems analysis, which consists, to put it simply, in describing and understanding how a system works. Any set of interacting events, things, or phenomena can be a system if it has input, output, and purpose. In order to make sense out of its complexity, we have to build a simplified model of the system, selecting only those details we need for clarity. This can be done with an actual smallscale model in the case of man-made systems, or it can be done mentally or with charts. * As the model of the system is tested it should be continuously corrected by experience, so that it will conform as closely to reality and need as possible. Once we understand it, we should be able to explain the system’ s past behavior so that it makes sense or predict its future behavior with a reasonable degree of accuracy. If our model for the system conforms to the actual reality of the system, our explanations will be clear and our predictions accurate. If our model happens to be insufficient or incorrect, our predictions and explanations will also be wrong, or insufficient. Living systems can be thought of as showing four specific characteristics: 5
• Wholeness and order. It is more than the sum of its parts, and the relationships between the parts more than the parts themselves determine the behavior of the system. For instance, a human being can continue to function without some parts( appendix or gall bladder, for example).
• Adaptive Self-Stabilization. Environmental disturbances will elicit reactions from the system that attempt to return it to normal. For instance, dust will provoke a sneeze.
• Adaptive Self-Organization. A constant disturbance to the system will cause it to attempt to reorganize itself so as to adapt to the interference. For instance, constant noises cease to be heard.
• Intra- and Inter-Systemic Hierarchies. Organisms are made up of systems of lesser complexity( for example, organs, cells) and are part of larger systems of higher complexity( for example, families, tribes, nations). Living systems are extremely complex because they consist of other systems. All higher animals, for example, include within their bodies the digestive, excretory, respiratory, reproductive, circulatory, nervous, and endocrine systems. Not only that, it is often almost impossible to draw the exact boundaries between one system and another or between one system and its environment. The digestive, excretory, respiratory, and reproductive systems, for example, intimately connect the larger system that is the body to the outside environment. Furthermore, living systems are unstable. They are constantly exchanging energy and matter with their environment. As a general rule, they are characterized by a strong tendency to return to“ normal,” to a“ steady state” or balance. But they can also be affected by input and disturbances in unpredictable ways. Disturbances, or“ perturbations,” when they reach a certain intensity, may trigger changes in a self-organizing living system that amount to a total reorganization. 6
Some examples: near-death experiences that totally change a person’ s life; drastic changes in diet that provide a dramatic new viewpoint; amino acids organizing themselves into living muscle tissue. The reorganization, incidentally, generally goes in the direction of higher order, coherence, and complexity— the