Complexity is acceptable as long as it is intelligible and necessary. We want to avoid needless complications.

Attractive things work better When you wash and wax a car, it drives better, doesn’t it? Or at least feels like it does.

Rule of thumb: if you think something is clever and sophisticated beware-it is probably self-indulgence.

We expert teachers know that motivation and emotional impact are what matter.

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

The world is complex, and so too must be the activities that we perform. But that doesn't mean that we must live in continual frustration. No. The whole point of human-centered design is to tame complexity, to turn what would appear to be a complicated tool into one that fits the task, that is understandable, usable, enjoyable.

In design it is important to shoe the effect of an action. ... Feedback is critical.