Cervantes and Shakespeare almost certainly never met, but the closer you look at the pages they left behind the more echoes you hear. The first, and to my mind the most valuable shared idea is the belief that a work of literature doesn’t have to be simply comic, or tragic, or romantic, or political/historical: that, if properly conceived, it can be many things at the same time.
Salman Rushdie on the similarities between Shakespeare and Cervantes. The two men died on the same day (not exactly, in fact, as Rushdie explains), and they have a lot in common.
And they are both as fond of, and adept at, low life as they are of high ideas, and their galleries of rascals, whores, cutpurses and drunks would be at home in the same taverns. This earthiness is what reveals them both to be realists in the grand manner, even when they are posing as fantasists…
Rushdie’s description of Hamlet is one of the most concise I’ve ever read:
As the play proceeds, it goes on metamorphosing, becoming by turns a suicide story, a murder story, a political conspiracy and a revenge tragedy. It has comic moments and a play within the play. It contains some of the highest poetry ever written in English and it ends in melodramatic puddles of blood.
Source: Salman Rushdie: how Cervantes and Shakespeare wrote the modern literary rule book