pull down to refresh

another area of computer science
That is a very apt way to describe Common Lisp. The Lisp family of languages are a true branch of computer science, because many things discovered via Lisp are only feasible to discover/learn via Lisp. As an example, consider this book:
Alan Kay called it "the best book anybody's written in ten years", and contended that it contained "some of the most profound insights, and the most practical insights about OOP", but was dismayed that it was written in a highly Lisp-centric and CLOS-specific fashion, calling it "a hard book for most people to read; if you don't know the Lisp culture, it's very hard to read".
The key bit is "Lisp culture". There are certain concepts learned by Lisp programmers that cannot be learned without learning Lisp.
One last example, consider LambdaLite, which is a database written in 250 lines:
what LambdaLite does would be impossible in most languages.