In Stacy Schiff's biography of Cleopatra, I came across this epigraph from Euripides: "Man's most valuable trait is a judicious sense of what not to believe."
I have no idea which of Euripides' plays the quote is from, but it strikes me as a suitable source for reflection.
Credulity is the default state of a human life. Children are born to believe, to accept as true what they are told by adults. An innate credulity has survival value in a dangerous world. If a grown-up says "There are crocodiles in the river," it is probably best to stay out of the water.
Skepticism, on the other hand, must be learned.
I was late in realizing that I didn't have to believe the received "truth." My best teacher was a somewhat older Panamanian secular Jew I went to graduate school with at UCLA. We took our brown-bag lunches together in the university's botanical garden, and spent the hour talking about physics, religion, and the "meaning of life."
Moises was the first person I had encountered after sixteen years of Catholic education who mentioned the word "skepticism." "Why do you believe that?" he would ask, and often I had no answer except that it was what my family and teachers told me was true. The idea that I might actually examine the basis for my beliefs was a rather new concept. In matters of religion, like almost everyone else in the world, I had embraced uncritically the faith story into which I was born.
And thus began my search for "a judicious sense of what not to believe." When later, as a teacher, I wrote a little column for each issue of the college newspaper, I called it Under a Skeptical Star, from a line of the Scots poet/scholar William MacNeile Dixon: "If there be a skeptical star I was born under it, yet I have lived all my days in complete astonishment."
A liberating sense of what not to believe opened the door to a vastly more interesting world whose diverse and astonishing riches I continue to explore to this day.