Many physicists have a high respect for string theory – in fact, the string theorist Ed Witten is often regarded as the greatest theorist alive. Yet critics, of whom there are many, call string theory an unscientific sham, arguing that it has no experimentally testable predictions and, barring a miracle, will have none for decades. For this reason, some physicists, such as Robert Ehrlich, have compared and contrasted the scientific status of string theory and intelligent design (Physics in Perspective 8 83).

But in String Theory and the Scientific Method, Richard Dawid – a physicist and philosopher from the University of Vienna – confronts these contradictory feelings head-on. Dawid seeks to amend orthodox philosophy of science, arguing that physicists can be on solid ground when drawn to a theory for reasons other than mere testability. He makes three arguments, and in the style of orthodox philosophy of science gives them acronyms: there may be no alternatives to the theory (NAA, for No Alternatives Argument), the theory may bring unexpected coherence or clarity (UCA), and its research programme may be analogous to others that have succeeded (the Meta-Inductive Argument or MIA).

Dawid makes other claims, such as that string theory is a plausible candidate for a final theory. But it was his amendments that grabbed my attention, for they allow me to illustrate two different approaches to the philosophy of science.

The game of science

The orthodox or “Anglo-American” approach (so-called because it was developed by British and American philosophers) regards the scientific method as starting with facts, moving to a theoretical level that can make predictions, and then – through experimental verifications – delivering facts to start anew. In his classic book A Philosopher Looks at Science, John Kemeny illustrates this approach – also called the deductive-nomological (DN) model – with a football-goal-like diagram. Induction (turning data points into generalizations) is like a post that rises from up the field of play (or “world of facts”). The post connects with a crossbar (the theoretical realm), which leads to a prediction – the verification of which returns via the other goalpost to the ground. Science’s strength depends on its regular earthly contact. As science is endless, Kemeny says, “we may expect this cyclic process to continue indefinitely”.

This orthodox approach emphasizes prediction and verification, but marginalizes other aspects of science, such as how discoverers reason and the context of discovery. To use another sporting analogy, it views science as about scoring; it focuses on scoring strategies and not on such things as how the game evolves, the attitude of its players, or its social role. To be scientific is to adopt optimal scoring strategies.

A contrasting approach – some branches of which are called Science Studies, while others are dubbed Continental because they were inspired by Continental thinkers – views science as a process of making sense of the world, but with a broader perspective to sense-making than prediction and discovery. Here, the scientific process involves scientists using existing concepts to understand what they discover in the lab. Anything truly puzzling – a new kind of particle or dark energy, say – requires scientists to revise and transform the concepts they’ve inherited in the light of the new discovery and everything else they already know. Developing a new theory is thus not like picking and choosing a wallpaper, but an interpretive process. Science is less a matter of testing lucky theoretical guesses than a continual reinterpretation that makes explicit what scientists already understand, partly but imperfectly, in the light of new discoveries.

This alternative approach does not begin by formulating optimal scoring strategies but by understanding what is happening in actual games. It respects both the special character of science and its connection with everyday life. Scientists are people, not robots, so how does scientific engagement with the world differ from, or intensify, everyday experience? Why did human beings opt to play this particular game, and what stance does the game require of its players? This approach sees scoring strategies as springing from this game, rather than dictating it. To be scientific is to bring nature into better focus – and there’s much more to this process than confirming theories.

The critical point

Partisans of the two approaches are generally unsympathetic to each other. I’ve read Anglo-American philosophers declare that the alternative approaches are grounded in subjective fictions. Meanwhile, a Continental colleague refers to Anglo-American philosophy as “the Fox News Network of the philosophical world”, satisfied with staying inside its bubble where “scientific reasoning leading to confirmation” determines what’s real, and snickering at other views.

Dawid’s book is remarkable in that, probably inadvertently, it combines aspects of both approaches. His philosophical training is Anglo-American, which disposes him to try to formulate a revised form of “the scientific method” that’s similar to the old one, but with amendments. We might call his approach a “Modified Orthodox Response” (MOR) that does whatever tinkering is needed to keep the orthodox approach from being blatantly out of touch with scientific practice. Yet his heart is with those whose understanding of science is informed by a more robust and experiential sense of scientific practice. The physics game he’s playing is going on just fine – even though it is missing a goalpost and has a very long crossbar that vanishes off the horizon. He’s disturbed enough by the mismatch between what his philosophical tradition tells him and the physics that he knows to try to reinterpret the former. Dawid wants to amend the scoring strategies of physics, not by improving their logic, but by adapting them to what he knows as a player to be happening on the field.

I call this progress in philosophy of science!