Isn't one of your first exercises in learning how to communicate to write a description of how to tie your shoelaces? The point being that it's basically impossible to use text to show that

A big ethical question is what happens after people stop using the device. Does it degrade the environment? Could it have been designed so it would actually be good for the environment?

The designer has an obligation to provide an appropriate conceptual model for the way that the device works. It doesn't have to completely accurate but it has to be sufficiently accurate that it will help in both the learning of the operation and also dealing with novel situations.

So what does a good teacher do? Create tension - but just the right amount.

I'm not a fan of technology . I'm a fan of pedagogy, of understanding how people learn and the most effective learning methods. But technology enables some exciting changes.

When you have trouble with things—whether it's figuring out whether to push or pull a door or the arbitrary vagaries of the modern computer and electronics industries—it's not your fault. Don't blame yourself: blame the designer.

I prefer design by experts - by people who know what they are doing