I retain a great deal of affection for environments like Squeak, like Emacs, where you can stand as high up or as low down as you like in the system. Emacs has

I retain a great deal of affection for environments like Squeak, like Emacs, where you can stand as high up or as low down as you like in the system. Emacs has primitives written in C, of course, and Squeak doesn't cooperate real well with the rest of the world, but it's still a very powerful idea. It makes me a little sad that one cannot learn Java programming by e.g. loading up Eclipse and saying "what's the code for this thing?", in the way that Squeak, Emacs, many Forths, R, and yes Symbolics Lisp permitted.