I attended a Common Lisp convention at MIT around the year they did away with the SICP course and replaced it with a course using Python to program robots. It c

I attended a Common Lisp convention at MIT around the year they did away with the SICP course and replaced it with a course using Python to program robots. It came up in the Q&A of one of the talks and the question got kicked to Sussman who was in the audience and gave an explanation. He said that it used to possible, practically speaking, to treat software like discrete components so that you can reason about how to combine the units and predict the result, etc. By contrast, much programming today is bodging together a bunch of libraries whose behaviors are often poorly defined or otherwise opaque so that one often enough has to treat them like black boxes against which you have to apply scientific reasoning to understand how to use and integrate it. Hence Python and robots. Presumably the new course teaches skills around managing this complexity, but the shift in model advocated -- from the metaphor of well-behaved discrete components in composition to opaque units whose inputs and outputs (possibly depending on hidden state) must be discovered was interesting to me, and ultimately adds to the accidental complexity of doing software now. Do you think this sort of problem may have a distinct visual representation that would fundamentally reduce the complexity of library-dominated development? Or are you imagining a whole programming ecosystem built around your idea, so that the fundamental problem Sussmen described is somehow obviated? Or are you really trying to address essential, not accidental complexity?