You seem to be a character in their lives. You feel your feet walking, your hands swinging. Tiny electrical impulses stimulate the sensual receptor centers of your brain, so that you smell freshly cut lawns on the summer breeze. You hear the wind in the trees. You get into a car. Julia/Alec is driving. You're slammed back against the seat by the sudden acceleration. You realize someone is chasing you. A slug slams into the window beside you, and glass flies against your cheek. You feel the cut. Blood runs down onto your hands, but Julia/Alec shouts, "It's only a flesh wound. Hang on!" And then the rocket car lifts off and zooms into the stratosphere, where your driver parks it in orbit, turns to you, smiles seductively, and says, "The moon really looks pretty from here. . . . "

These kinds of escapist experiences will be available, I understand, within a generation. Crude forms of them are available now. Virtual reality is an academic specialty, but movies like "Tron" and "The Lawnmower Man" are introducing the concept to mass audiences.

The questions about VR fall into two categories: technical and ethical. The technical questions will take care of themselves; this technology will be perfected. But the ethical questions are extremely interesting. They include:

To what degree is it permissible to completely take over another person's consciousness? Is there a limit to how deeply one person should manipulate another's experience? Is it right for us to have VR experiences before we have actual experiences to base them on? What would it mean if we had our first sexual experience in VR before we had it in real life?

If we really and truly felt we were dying in VR, how would that affect our subsequent life, after we "awakened"? If we were completely convinced of impending death, could a real "near death" experience be triggered? Would all our loved ones beckon us to enter that famous tunnel of light, only to discover it was a false alarm?

And what would it be like for the stars? There'd be millions of people walking around who, thanks to Vrovies, shared the literal impression of having made love with them, killed them, been killed by them, spent time with them? If a fan said, "I loved you in your last Vrovie," what would the correct answer be?