[Discovering] things is much more gratifying if there has been some difficulty in the search for them. Those, after all, who never discover what they are looking for suffer from starvation, while those who do not have to look, because everything is ready to hand, often start wilting out of sheer boredom; in either case, a malady to be avoided.

— St. Augustine (tr. Edmund Hill, O.P.), Teaching Christianity (De Doctrina Christiana) 2.8. He is speaking about the interpretation of Scripture, and particularly of the “innumerable obscurities and ambiguities” (2.6.7); but there are many applications of this word.