We do not think of the object as an "interface" to a program running on a "computer”. We think of the object itself as running the program, noticing and communicating with the objects around it. Of course there must be electrical hardware to make this work. An analogy might be reading a book at night with a lamp. We do not think of the book as an "interface" to words coming from the lamp. (Although the photons might think of it this way.) We think of the lamp as creating an environment in which words can come from the book. Likewise, Realtalk hardware creates an environment in which physical objects exhibit dynamic behavior.
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