New Delhi, May 18 -- "The fool doth think he is wise, but the wise man knows himself to be a fool."

William Shakespeare wrote this line for a comedy. But it contains one of the most serious ideas he ever put on stage. It appears in As You Like It, spoken by the character Touchstone. The play is full of wit and wordplay. Yet this single line cuts deeper than almost anything else in it.

The structure of the line is the point. Two types of people. Two completely opposite relationships with knowledge. The fool is certain. The wise man is uncertain. And Shakespeare suggests, without hesitation, that the uncertain one is the wiser of the two.

This is not a comfortable idea. Certainty feels good. Doubt feels unsettling. And yet the line insis...