EARLY PHILOSOPHICAL THEORIES ABOUT SCIENCE Philosophers of the late Renaissance were optimistic about humanity''s ability
to understand and control the natural world. During the 17th centuryÑthe era of Galileo Galilei, William Harvey, Sir Isaac Newton, and Robert BoyleÑscientists and philosophers alike were convinced that with the help of the newly discovered scientific method modern scientists would quickly surpass the achievements of their Greek and medieval predecessors. Disagreement existed, however, as to the details of the correct scientific method. Rationalism In his Discourse on Method (1637), RenŽ Descartes asserted that all theoretical science should be like Euclidean geometry. A science such as physics should be based on first
principles comparable to the axioms of geometry, which were discovered and validated through the systematic analysis of intuitive ideas. Descartes thought, for example, that the law of inertia could be seen to be true through the use of reason alone. This view, that science can be based on principles that are revealed through introspection, is called rationalism (from the Latin ratio, "reason"). An objection to the rationalist approach to science is that people''s intuitions about fundamental scientific propositions do not always agree. Furthermore, especially in the social sciences, trying to base scientific principles on introspection alone has led to social injustice as well as to scientific stagnation. Early European anthropologists, for example, thought it self-evident that non-Europeans were inferior both in intelligence and in personality development. Their uncritical acceptance of the view that the people they called "savages" were either animals or, at best, children seriously inhibited both scientific and social progress. Empiricism The English philosopher Francis Bacon, whose New Organon appeared in 1620, also believed that there was a rigorous "organ," or method, for making scientific discoveries, but his theory of method was quite different from that of Descartes. Bacon believed that instead of analyzing intuitive ideas, scientists should first empty their minds of all preconceptions and then make
observations. By using inductive logic one could generalize from these observations about particular cases. In this way one would finally arrive at the most fundamental and comprehensive laws of nature. This view of scientific methodology, that all scientific knowledge is derived from observation alone, is called empiricism (empeira is the Greek word for "experience"). Bacon''s theory of method may seem much more plausible than Cartesian rationalism, especially to Anglo-Americans who have been brought up in an atmosphere strongly influenced by empiricism. Nevertheless, Bacon''s approach has serious inadequacies. In contrast, philosophers in the tradition of Immanuel Kant have argued that it is impossible to make observations that are free of all preconceptions, as Bacon would have us do, because all observational reports go beyond what has actually been perceivedÑor, in modern terms, all observations are "theory-laden." Furthermore, Bacon''s claim that all scientific laws are the result of inductive generalizations from statements of observation is not correct. If scientists were in fact strict Baconians, there would not be any theoretical science. Adherence to Baconian inductivism can also result in inaccurate social judgments, and in fact much of what is called superstitious reasoning is based on a form of naive empiricism.