[daslu]

One important detail is that in Lisps like Clojure, printed values can usually be read back as code. So, the REPL is really a read-eval-print-LOOP.

Another detail is that the whole culture of the language, oriented towards immutable data, makes it very easy to evaluate almost any sub-expression in your code, which makes the whole code introspectable in a very playful and dynamic way.

[dionian]

I never got deep into any lisp like language but this was one of my favorite aspects of them - homoiconicity.