A dynamic new school of thought is emerging that wants to kick down the walls of recent philosophy and place experimentation back at its centre. It has a name to delight an advertising executive: x-phi. It has blogs and books devoted to it, and boasts an expanding body of researchers in elite universities. It even has an icon: an armchair in flames. If philosophy ever can be, x-phi is trendy. But, increasingly, it is also attracting hostility.
Philosophers have always been informed by scientific research, history and psychology. Indeed, most of the giants of pre-20th century philosophy combined empirical and conceptual studies. Some drew on the research of others, while René Descartes and John Locke performed their own experiments; this was a time when science had not entirely split from philosophy. David Hume mixed reason with experience, including psychological and historical observations alongside more abstract reasoning—A Treatise of Human Nature was subtitled “Being an Attempt to Introduce the Experimental Methods of Reasoning into Moral Subjects.”
But for many philosophers today the idea of experimental philosophy still grates. Conceptual analysis has been a dominant strain of Anglo-American philosophy in the past 100 years. Philosophy of this kind considers not so much how things are, but rather how we think about them: the way we carve up the world, the frontiers of meaning, of what makes sense. But for the x-phi fan, empirical research is not a mere prop to philosophy, it is philosophy.
Under the x-phi banner it’s possible to distinguish three types of activity. The first uses new brain-scanning technology, for which philosophers teaming up with neuroscientists, like Katja Wiech, to look for patterns of neuronal activity when subjects are presented with philosophical problems. In the second type, philosophers devise questionnaires to discover people’s intuitions and go out in the street with the trusty clipboard. In the third, they conduct field experiments, observing how people behave in particular situations, often without their knowledge. All three aim to test the philosophers’ assumption that they know from introspection what people are likely to say or believe. The traditional philosophical assertion, “we have strong intuitions that…” or “we can all agree that…” now have to be tested against the evidence.