Thesis 77

Everyware must be deniable.

Our last principle is perhaps the hardest to observe: Ubiquitous systems must offer users the ability to opt out, always and at any point.

You should have the ability to simply say "no," in other words. you should be able to shut down the ubiquitous systems you own and face no penalty other than being unable to take advantage of whatever benefits they offered in the first place. This means, of course, that realistic alternatives must exist.

If you still want to use an "old-fashioned" key to get into your house, and not have to have an RFID tag subcutaneously implanted in the fleshy part of your hand, well, you should be able to do that. If you want to pay cash for your purchases rather than tapping and going, you should be able to do that too. And if you want to stop your networked bathtub or running shoe or car in the middle of executing some sequence, so that you can take over control, there should be nothing to stand in your way.

In factand here is the deepest of all of the challenges these principles impose on developers and on societieswhere the private sphere is concerned, you should be able to go about all the business of an adult life without ever once being compelled to engage the tendrils of some ubiquitous informatic system.

In public, where matters are obviously more complicated, you must at least be afforded the opportunity to avoid such tendrils. The mode of circumvention you're offered doesn't necessarily have to be pretty, but you should always be able to opt out, do so without incurring undue inconvenience, and above all without bringing suspicion onto yourself. At the absolute minimum, ubiquitous systems with surveillant capacity must announce themselves as such, from safely beyond their fields of operation, in such a way that you can effectively evade them.

The measure used to alert you needn't be anything more elaborate than the signs we already see in ATM lobbies, or anywhere else surveillance cameras are deployed, warning us that our image is about to be capturedbut such measures must exist.

Better still is when the measures allowing us to choose alternative courses of action are themselves networked, persistently and remotely available. Media Lab researcher Tad Hirsch's Critical Cartography project is an excellent prototype of the kind of thing that will be required: it's a Web-based map of surveillance cameras in Manhattan, allowing those of us who would rather not be caught on video to plan journeys through the city that avoid the cameras' field of vision. (Hirsch's project also observes a few important provisions of our principle of self-disclosure: His application includes information about where cameras are pointed and who owns them.)

All of the wonderful things our ubiquitous technology will do for usand here I'm not being sarcastic; I believe that some significant benefits await our adoption of this technologywill mean little if we don't, as individuals, have genuine power to evaluate its merits on our own terms and make decisions accordingly. We must see that everyware serves us, and when it does not, we must be afforded the ability to shut it down. Even in the unlikely event that every detail of its implementation is handled perfectly and in a manner consistent with our highest ambitions, a paradise without choice is no paradise at all.