This quotation (in many variants) is so ubiquitous as it is meaningless, but it is still interesting to find its source: Saul Bellow, The Distracted Public, 1990

A professor in California has estimated that on an average weekday the New York Times contains more information than any contemporary of Shakespeare would have acquired in a lifetime. I am ready to believe that this is more or less true, although I suspect that an educated Elizabethan was less confused by what he knew. He would certainly have been less agitated than we are. His knowledge cannot have lain so close to the threshold of chaos as ours.

Though, I have no idea who that "professor in California" is. Quote found here