The same thrill, the same awe and mystery, come again and again when we look at any problem deeply enough. With more knowledge comes deeper, more wonderful mystery, luring one on to penetrate deeper still. Never concerned that tht answer may prove disappointing, but with pleasure and confidence we turn over each new stone to find unimagined strangeness leading on to more wonderful questions and mysteries — certainly a grand adventure!

Richard Feynman (1918–1988) American physicist

Speech (1955-11), “The Value of Science,” National Academy of Sciences Autumn Meeting, California Institute of Technology
    (Source)

Collected in (1955-12), "The Value of Science," Engineering and Science, Vol. 19