I love this quote ...
Lisp has jokingly been called "the most intelligent way to misuse a computer". I think that description is a great compliment because it transmits the full flavor of liberation: it has assisted a number of our most gifted fellow humans in thinking previously impossible thoughts.
-- Lisp Quotes
... and that phrase - "thinking previously impossible thoughts" - sums up what it means to learn. All progress - whether scientific, political, social or in any human endeavour - asks us to think previously impossible thoughts.