AOP also encompasses techniques you can't find in CLOS/MOP. The analogues to before/after/around methods are the easiest concepts to implement and reason about,

AOP also encompasses techniques you can't find in CLOS/MOP. The analogues to before/after/around methods are the easiest concepts to implement and reason about, so those are what popular language extensions tend to emphasize. But if you look at the original AOP papers describing Reverse Graphics, you'll see an AOP system used to liberally restructure the control flow of the entire base program, not just augment its behavior. It was an early version of what you can see now in something like the Halide language. > I believe MIT first year CS switched to Python in part to deal with this resistance. In part. The full story is a bit more depressing: http://www.wisdomandwonder.com/link/2110/why-mit-switched-from-scheme-to-python http://www.wisdomandwonder.com/link/2110/why-mit-switched-fr... Most of the other top universities that had used SICP also switched shortly after MIT.