[shiro]

Don't confuse lisp-as-an-executable-device-to-think-meta and lisp-as-one-of-programming-language-choices. Alan is talking the former.

The idea---not just to think about programs per se, but to think about abstract properties and operations of certain category of programs and to be able to actually write it down---gave the exponential power to you. Lisp was the first such tool as a programming language that allowed you to break the ceiling of first-order thinking.

Nowadays there are other languages that provide meta-level tools. And once you get the idea, the language doesn't really matter; you can apply it to any language, albeit you may have to build scaffolds around it to compensate lack of language support (Cf. Greenspun's tenth rule). So, if you already got the idea through other languages, it's good for you. You'll see Lisp as an arcane prototype of modern languages.

But note: since Lisp can write meta-level description in the same language as the base language, you can top up this ladder infinitely, meaning you can think of program-generating-program, then program-generating-program-generating-program, and so on, using a single set of tools. It is indeed powerful but somewhat crude, so modern advanced languages intentionally restrict that aspect and just try to cover the sweet spot. Even if you're familiar with metaprogramming, it may still be worth to play with Lisp to see what (meta)*programming is like, to know its pros and cons, and to get the idea that might come handy someday when single-level metaprogramming isn't enough.