What is interaction? As a non-native English speaker, I started from looking up dictionary to answer this question.
The word seems to be popular since 1960s. Sketchpad (a.k.a. Robot Draftsman) was a revolutionary computer program written by Ivan Sutherland, It pioneered the way for human–computer interaction (HCI) in 1963.
So, How would I define physical interaction? What makes for good physical interaction?
After first class of Physical Computing and reading both Chris Crawford and Bret Victor’s articles, my answer is: Physical interaction is similar as I/O process, but cycling. It is a cyclic process in at least two actors alternately in five senses (taste, sight, touch, smell, and hearing) and there is a black box to generate reactions or feedback to each other.
In Bret Victor’s article, he mentioned a term called Pictures Under Glass. He stated it that Pictures Under Glass sacrifice all the tactile richness of working with our hands, offering instead a hokey visual facade.
I believe that it is because the limitation of technology. For example, we still used to create 3D objects in a 2D environment. But, it is not instinct. By latest technology, people can do the same work in an interactive way like Google Blocks.
So, I think a good physical interaction not only need to be intuition, but also keep in mind that reactions are hard to fake; feedback is hard to give.