[brudgers]

A person off the street gets the idea of a recipe. Most will get the idea of a process for taking a list of ingredients and producing a new recipe. But the idea of a procedure that takes a procedure for taking a list of ingredients and produces a recipe, and produces a new procedure for...etc. [I need some parentheses].

It's not the syntax of Lisp that is hard to learn. Nor is it the language primatives. What makes Lisp hard is the expressiveness of their idiomatic usage.

What makes Lisp difficult is how quickly one gets to abstract mental constructs like recursive definitions and procedures which take procedures as arguments - all before macros and meta-linguistics. That's saved for after lunch.

The worst part is that Lisp makes it look simple. A few micrograms can create a mind blowing experience.