Richard Rorty on Saul Kripke, 2005

“Who knows? How could it matter?”

As I see it, Kripke’s lectures in 1970 aroused the interest they did not because people cared all that much about which truths should be called necessary and why, but because they cared a lot about whether truth is correspondence to reality. Philosophers are still, just as they were in Russell’s day, very worried about whether there is any clear sense in which our beliefs about the world are like maps – whether they are somehow isomorphic to the pre-existing contours of reality (whether, in Plato’s metaphor, they ‘cut nature at the joints, like a good butcher’).

Common sense takes for granted that there is such isomorphism – that just as bits of a reliable map can be paired off with bits of a landscape, so the terms of a true scientific theory can be correlated with features of the way things really are. But those who think that all essences are nominal point out that such pairing was easier when, as in Aristotle’s time, the objects of scientific inquiry were observable things such as stars and animals. It got harder when Newton began talking about unobservables such as force, mass, and acceleration, and harder still when Planck began talking about quanta. Is ‘force’ the name of a natural kind? Is ‘Hilbert space’? Do these terms cut nature at the joints? Who knows? How could it matter? The more unobservables science posits, the less relevant the notions of ‘mapping’ and ‘corresponding to reality’ seem.

However, many philosophers fear that if we cannot specify some sense in which our scientific theories map onto reality in the same way as do perceptual reports (‘the cat is on the mat’), we are in danger of losing touch with the world. We may be tempted to become instrumentalists, people who think that we should accept scientific theories simply because they give us what we want (roughly, prediction and control of the environment), rather than because we think they accurately represent the real. For those who had such fears, Kripke’s neo-Aristotelian outlook had great appeal. Quine’s holistic claim that ‘the unit of empirical significance is the whole of science’ (rather than individual words or sentences) had done a lot of damage to the notion of ‘correspondence’. So had Kuhn’s denial that scientific progress is a matter of getting closer and closer to the true nature of things. Kripke’s willingness staunchly to oppose the drift toward pragmatism that characterised analytic philosophy during the 1960s won him an enthusiastic audience.