Sebastien de Castell explains why you need both in a very nice post at Fantasy Faction.

Shakespeare’s Julius Caesar is a tragic play fraught with intrigue, betrayal, and murder that makes us question the very foundations of human nature.

It starts with a joke.

To be more precise, the first scene is a series of puns in which a nobleman is made ridiculous to the audience by a cobbler who refers to himself as a ‘mender of soles’ (which, of course, the nobleman hears as ‘souls’.) It’s a remarkably clever scene that no doubt set the audience of the Globe Theatre in 1599 falling out of their seats from laughter. But what follows is the destruction of friendships, the breakdown of civil society, and an unending series of killings until the world of the play becomes utterly desolate. So why on earth does Shakespeare start with a joke?