Peter Hacker's Challenge to Neuroscientists: Make Sense!

Peter Hacker is an eminent English philosopher, an expert on Wittgenstein, and an outspoken critic of neuroscience as it's practiced and talked about today. In this accessible and entertaining interview in James Garvey's excellent The Philosophers' Magazine, Hacker explains his point of view: that neuroscience, and the philosophy that's based on it, has "stepped over the bounds of sense." As he explains to Garvey,

On the current neuroscientist’s view, it’s the brain that thinks and reasons and calculates and believes and fears and hopes. In fact, it’s human beings who do all these things, not their brains and not their minds. I don’t think it makes any sense to talk about the brain engaging in psychological or mental operations.

If you've never met a thinker like Hacker before, it might sound like he's stepped over the bounds of sense - but it's worth taking some time to see where he's coming from, since, as he puts it, "You just have to listen to the BBC to hear people nattering on about their brains and what their brains do or don’t do." So what is Hacker talking about? Here's a simple explanation.

Hacker, despite his recent turn towards neuroscience, has devoted his philosophical life to the study of Ludwig Wittgenstein. Wittgenstein's main interest was in language, and in the ways that, by talking about things, we can both clarify and confuse them. Everyone knows how you can talk yourself into a tangle, or, by figuring out a new way of talking about something, talk yourself out of one.

For Wittgenstein, and so for Hacker, it's always important to know whether what you're saying is clarifying things or confusing them - whether it's helping us solve a problem, or has stepped over the bounds of sense and is making the problem worse. Really hard problems are hard to talk about, and so it might take a long time and a sustained mental effort to figure out whether you're making sense or not. Think of what it's like to go to a therapist: it takes a while to figure out the specific ways in which you've gotten yourself all knotted up inside.

Philosophers, from this point of view, are a little like therapists: they discover what makes sense and what doesn't by listening to the way people talk. They try to communicate their sense of what makes sense to others in their writing - but, as anyone knows who's tried to 'talk sense' into anyone else, in the end each person has to figure out what makes sense for himself.

So why is Peter Hacker trying to talk sense into neuroscientists? Because he thinks that they're talking their way into a tangle by attributing lots of human actions - thinking, feeling, knowing, deciding, and so on - to the brain. His question is: does saying that 'your brain' decides something get you any closer to understanding what's happening when you decide? And his answer is that it doesn't. As he sees it, saying that 'your brain' decides something doesn't make sense, because brains don't decide, think, feel, or know; people do these things with their brains. Saying that 'your brain' decides is just another way of saying that you decide - but you knew that already. It would be bizarre, after all, if you decided, thought, felt, knew, and imagined with something other than your brain.

Hacker's perspective might seem nitpicky to you. But it might be just what the doctor ordered if you're suffering from neuroscience fatigue: the creeping feeling that, after reading zillions of articles and books about your brain, they've stopped making sense to you. You're not alone - one of the great things about neuroscience is that it's still grappling with fundamental questions and figuring out what it wants to say. Making discoveries is, in a way, easier than making sense of them. And the interview is an education in philosophy all by itself, with explanations and discussions of the work of Thomas Nagel, Daniel Dennett, and Wittgenstein - a sort of primer on the philosophical and conceptual confusions that have accompanied the last few decades of discoveries about the brain.

Photo: Peter Hacker, by Chris Elenbass of the British Wittgenstein Society.