I'm headed to the bookstore/library to pick up a copy of "The Sound and The Fury" by Faulkner. However, I took a look at two Faulkner books that I own, "Absalom, Absalom!" and "As I Lay Dying". On the back of the books there are a few critic's praise of Faulkner:
"For all his concern with the South, Faulkner was actually seeking out the nature of man. Thus we must turn to him for that continuity of moral purpose which made for the greatness of our classics." -- Ralph Ellison
"For range of effect, philosophical weight, originality of style, variety of characterization, humor, and tragic intensity [Faulkner's works] are without equal in out time and country." -- Robert Penn Warren
I believe similar things were said, and have been said of Shakespeare. One of the main reasons his works have lasted the test of time is because through his characters and plots human nature is exposed. This is why his plays are easily related as a reader.