Caspar Hare, associate professor in the Department of Linguistics and Philosophy. Image: Patrick Gillooly

(PhysOrg.com) -- Caspar Hare would like you to try a thought experiment. Consider that 100,000 people around the world tomorrow will suffer epileptic seizures. "That probably doesn't trouble you tremendously," says Hare, an associate professor in MIT's Department of Linguistics and Philosophy.

Now imagine that one those 100,000 people will be you. "In that case you probably would be troubled," observes Hare, speaking in his office. If this is your reaction, he says, "You regard you own pleasures and pains as being especially significant." Which seems natural, Hare adds. "We have a tendency to think that what we care about is important in and of itself."

Yet this tendency creates an apparent inconsistency. You cannot claim your own well-being is uniquely meaningful, more important than the well-being of others, and expect anyone else to regard that notion as an objective fact, something that could be part of a universally acceptable morality.

How should we reconcile these differing perspectives? In recent decades, many philosophers have dismissed our self-interest as a kind of illusion. Indeed, a major current of contemporary thinking has questioned whether a stable "self" exists at all. "We are not what we believe," the British philosopher Derek Parfit has written. Rather, this view holds, we are nothing more than ever-shifting collections of mental and physiological states, lacking a definite, lasting identity.

The joy of solipsism

Hare has leaped into this philosophical fray with a distinctly different view, which he outlines in his new book, "On Myself, and Other, Less Important Subjects," published this fall by Princeton University Press. The fact that we care so much about ourselves, Hare thinks, tells us something deep about the world: It is correct after all, he believes, to regard our pleasures and pains as uniquely important among all pleasures and pains in the universe.

So if we think our self-interest is singularly significant, we are not being fooled. Instead, the fact that we know ourselves best reinforces our sense of individuality over time; we do have stable identities, and our minds are more than a shifting kaleidoscope of impressions. Our ability to make moral judgments flows from this fact.

On the other hand, Hare asserts, our minds are independent enough from the rest of the world that, when other people state their pleasures and pains are present, we should not regard their statements as true. Instead, Hare writes, we should regard those claims as "false, but rightly so."

In so arguing, Hare is reviving the philosophical concept of solipsism — the notion that one's own self has a special status in the world. More specifically, Hare claims in his book that we exist in a mildly solipsistic state he calls "egocentric presentism." To make sound moral judgments despite this condition, Hare asserts, just takes an act of imagination.

Thus Hare states that of course he would rather that he suffer a hangnail than that someone else's leg be crushed, even knowing the other person's pain would not be present. "For an egocentric presentist," writes Hare, "empathizing with an unfortunate [person] involves imagining that the unfortunate has present experiences."

Other philosophers note that Hare's ideas appear counterintuitive. "The argument seems controversial on the surface because it goes against common sense," says Berit Brogaard, an associate professor of philosophy at the Australian National University and the University of Missouri, St. Louis. "There is something eyebrow-raising about it," says Benj Hellie, an associate professor of philosophy at the University of Toronto.

Hare, however, does not think his own theory is radical. "One way to be a solipsist is to insist that other people don't have inner lives," explains Hare. "Another is that there are no other people. But I'm not saying either of these things. I'm not denying that other people exist, are fully conscious, and have brains and minds like my own."

Is universal morality possible?

For this reason, asserts Hare, solipsism need not lead us down a slippery slope into a world where, say, violence toward others could be tolerated. "Even if we give special significance to our own pleasures and pains," says Hare, "we don't go about ruthlessly trying to maximize our own pleasure and others' pain." He calls that "a crude caricature of human psychology," popularized by the 17th-century English philosopher Thomas Hobbes.

We may be self-centered, Hare argues, but not solely moved by self-interest: "It's certainly possible to think your self-interest is important without thinking it's the most important thing in the world." Still, Brogaard, for one, thinks Hare's ideas "are even more extreme" than Hare believes they are. By accepting that we are solipsistic, she believes, we may sacrifice the idea that there is an objective universal morality.

If so, the modestly solipsistic state Hare describes — in which we are still social and moral creatures — represents a trade-off. We may lose our ability to define an objective moral system. But we do have stable selves that can craft moral judgments. "My book is putting perspectival questions back into the ontology, into our picture of the way the world is," says Hare.

That still leaves the task of squaring our recurring self-interest with the common good, day after day. But that is at least a task for which we can each take responsibility, as distinct selves. "Caspar is pointing to a problem we have to come to terms with," says Hellie.

Provided by Massachusetts Institute of Technology (news : web)

Explore further Man's best friend lends insight into human evolution