We, Elena and Mary, are creating learning resources here for CS333 Programming Languages. If you are interested in the functional paradigm, read about Lisp. If you want to learn about the logical paradigm, check out Prolog. It is really fascinating to learn how to think in these non-imperative paradigms, so have fun, and don't get discouraged if you do not immediately understand!
Common Lisp – Functional Paradigm
"Lisp is worth learning for the profound enlightenment experience you will have when you finally get it; that experience will make you a better programmer for the rest of your days, even if you never actually use Lisp itself a lot."
- Eric Raymond, "How to Become a Hacker"
Prolog – Logical Paradigm
"Declarative programming clears your mind. Said less dramatically, programming one's ideas in general, and programming in a declarative and high-level language in particular, clarifies one's thoughts and concepts. Prolog is . . . a formalism in which ideas can be expressed and evaluated - a tool for thinking. "
--Leon Sterling and Ehud Shapiro, The Art of Prolog