Will robot teachers replace human teachers? No, but they can complement them. Moreover, the could be sufficient in situations where there is no alternative––to enable learning while traveling, or while in remote locations, or when one wishes to study a topic for which there is not easy access to teachers. Robot teachers will help make lifelong learning a practicality. They can make it possible to learn no matter where one is in the world, no matter the time of day. Learning should take place when it is needed, when the learner is interested, not according to some arbitrary, fixed schedule

Could we ever switch to this or any of the many other rational systems? Unlikely: tradition is difficult to overcome.

What makes something simple or complex? It's not the number of dials or controls or how many features it has: It is whether the person using the device has a good conceptual model of how it operates.

adults forget how difficult that task was.

Any time you see signs or labels added to a device, it is an indication of bad design: a simple lock should not require instructions.