Excellent point. I found myself struggling to describe Lisp in terms that non-Lispers would understand (blub paradox I guess), and I figured almost everyone kno

Excellent point. I found myself struggling to describe Lisp in terms that non-Lispers would understand (blub paradox I guess), and I figured almost everyone knows what a REPL is. You're absolutely right that a REPL itself is just scratching the surface, and there is all kinds of interactivity beyond that.