The virtual explosion in the amount of biomedical information, the switch away from a lecture-based style of teaching, and the perception that more of the student's time should be directed to patient-oriented activities have created an intense competition for time in the undergraduate medical curriculum. Our objectives are to impart an enthusiasm for learning together with an improved capacity to understand concepts and the ability to solve problems in clinical medicine. We rely heavily on the deductive capacities of the student. We shall emphasize horizontal (basic) and vertical (clinical) integration of disciplines that relate energy metabolism with fluid, electrolyte, and acid-base balances. The setting in which we begin to define a problem is in "Paleolithic times" because this is when metabolic control systems evolved and were most likely to be retained. Students are asked to deduce the best possible solutions for that problem, to ask for data to test their hypotheses, and to consider the ramifications of that solution in integrative terms. Subject matter is presented by informed leaders in either a small or large group format initially to set the stage. An interactive computer program was written as a supplement to demonstrate how we would utilize the information and concepts to design an element for teaching. The implications are that controls that were designed for primitive needs may lead to disorders in modern times because the current stimuli and needs are different. The power of the student's growing ability to solve problems should be reinforced by demonstrating the degree to which the properties deduced by the student to solve a particular problem are actually consistent with data from the literature.