Often discussions of “science and religion” have focused more on the philosophy of science than on the content of science. That is due in part to the fact that until recently theologians were more likely to have a background in philosophy than in the natural sciences. In any case, questions about what constitutes legitimate scientific work and “the scientific method” do need to be examined as part of science-theology dialogue.
I would begin by saying that it is not philosophers but scientists themselves who should be consulted first about what constitutes good science.
Many scientists would endorse a statement made a century and a half ago by Claude Bernard in An Introduction to the Study of Experimental Medicine (Dover, 1957). Speaking of those who try to set out systematized rules for scientific research, Bernard said,“…works like theirs are of no use to experienced scientists; and by false simplification of things, they mislead men who wish to devote themselves to cultivating science.”
This is not to say that philosophers of science have nothing to contribute, but, as in theology, philosophy must have a ministerial and not a magisterial role in science. It certainly can help us to understand what theoretical and experimental scientists are doing and try to guard us against faulty reasoning. If we want to know what science is, however, we must first look at how science operates in order to gain its knowledge of the world.
You can Google “scientific method” and find a number of descriptions of what this method is supposed to be. Many are good, but we should not make the mistake of thinking that there is an official “scientific method” in the sense of a precise recipe that a person must follow in order to be a good scientist. Science involves the continued honest use of observation and reason — not necessarily in that order! (Albert Einstein’s “On the Method of Theoretical Physics” in Essays in Science [Philosophical Library, 1934] is a good presentation of this view and introduction to his thought.) Some scientists are pure theorists, but their theories must hold up when confronted with observation. Other scientists focus on the observational aspect, but theory is needed to make sense of the data that they obtain.
Reason and observation should be understood in quite general ways. Reason may involve very rigorous logic and/or advanced mathematics, but it also includes intuitive leaps. The famous story of the German organic chemist Friedrich August Kekulé von Stradonitz (1829–1896) dreaming about the structure of the benzene ring is an example. (But he had been thinking about the problem for awhile, and he later reminded his fellow scientists not to publish their dreams until they’d been tested by their waking minds.) Observation means the use of all our senses, often enhanced with scientific instruments (which require theoretical understanding). In particular, it includes the type of controlled observation that we call experiment.
To this point I may have given the impression that I envision scientists as purely objective entities who investigate an external world in an entirely neutral way in order to discover how that world really is. That sort of naive realism is hard to maintain today for several reasons. At the quantum level, what the observer chooses to observe has some influence on what takes place. And on all scales, gender, race, economic status, religion, and other cultural factors influence the processes of observation and theory construction. This has led some postmodernists to argue that science has no better claim to find truth about the world than any other cultural enterprise does.
Public Character of Science
Popular as such views may be among some nonscientific academics (who write their essays on word processors that are products of science-based technology), they are greatly overstated. The factors I’ve mentioned do influence science, but science has, at least in principle, features that can correct for cultural bias. Prominent among them is the public character of science. We should not be naive about our supposed objectivity or the truths that we seek to discover, but a critical realism is — well, realistic. As physicist John Barrow put it in The World within the World (Oxford, 1988), “Almost every working scientist is a realist — at least during working hours.”
Just saying “observation and reason” is pretty general. A more detailed description (not prescription) of the way science works has been given by Imre Lakatos. A basic concept here is that of a research program in science. Such a program has a fundamental theory, a “hard core,” which practitioners attempt to apply and which they try to defend against challenges. Certain auxiliary theories constitute a “protective belt.” If observations require it, the theories of the protective belt can be modified in order to keep the hard core intact.
The goal of a research program is not just to maintain its hard core but to extend the range of the program’s explanations by predicting novel facts, which are then confirmed by observations. A program that can do this while retaining its previous successes is progressive. A program that produces no successful predictions but can only accommodate new data by modifying its protective belt is regressive. Programs that are progressive at any given time will be those we consider good current science.
Naturalism — Two Kinds
What is the role of religion in science? Some would answer that it has none, but that is too drastic. Religious beliefs can motivate people to engage in science (and, unfortunately, sometimes to avoid it). They may suggest to some scientists lines of investigation that might be fruitful. And certainly a person’s beliefs will have an influence on what she or he considers ethical means of research and applications of science.
But since the seventeenth century it has been a working rule among scientists that natural phenomena are to be explained in terms of natural agents and causes. No scientist, whatever his or her religious beliefs, will explain a puzzling result of an experiment by saying “God did it.” A Christian who holds a traditional view of creation will believe that God did do it. The scientific question, however, is “How?”
This working rule is what is often called methodological naturalism. It is not a claim that science can explain everything but rather a limitation of science to the study of the natural world. This should not be (though it often is) confused with metaphysical naturalism, the belief that there is nothing other than the natural world.
Methodological naturalism is central to current debates about Intelligent Design (ID). While ID proponents sometimes say that they are opposed simply to “naturalism,” what the ID movement is arguing for is the inclusion of a nonnatural agency (the “designer”) in scientific theories of the development of life. Whether or not ID is to be called science depends on whether the traditional restriction of science to natural causes is to be maintained. But even if, for the sake of argument, we call it science, ID has not yet shown itself to be a progressive research program.
Nancey Murphy, in Theology in an Age of Scientific Reasoning (Cornell, 1990), describes Lakatos’s approach and applies it to theological method. Del Ratzsch, in Philosophy of Science: The Natural Sciences in Christian Perspective (InterVarsity, 1986), gives an introductory overview.