Introduction

Abstract

Medicine is the science of intervention. Among human activities, medicine is rivaled only by agriculture (and more recently by modern engineering) in its capacity of changing the natural course of human fate. To intervene, however, one must predict. To predict the natural course of a system in the absence of intervention and to predict what is going to happen to such a system after the proposed intervention. Prediction, in turn, is strongly dependent on the scientific foundations of the subject in question. Although medicine men have been intervening in human diseases since the dawn of humanity (actually with rather questionable results) only very recently the scientific cornerstones of medicine have been laid down. After several centuries as a set of empirical practices, medicine gained some taints of natural history in the 19^th century and only in the first half of the 20^th century it overpassed the epistemological threshold. In the last 50 years, medicine started its approach to the formalism threshold, which is characterized by the application of formal logic and mathematics to the theoretical bases of diseases. Therefore, the marriage between mathematics and medicine is very recent and it started rather timidly with the works by the fathers of epidemiology. Scattered applications of mathematics in some biomedical areas was found in the literature until the early 1970s. Since then however, mathematical biology has changed a great deal. The magnificent 100 volumes of the series Lectures Notes in Biomathematics edited by Simon Levin is a respectable witness of those changes. In medicine specifically, mathematical models have been developed for some diagnostic problems and, to a great extent, to epidemiological questions.