<P> In his own earlier work, The Merchant of Venice, Shakespeare also had one of his main characters, Antonio, comparing the world to a stage: </P> <P> I hold the world but as the world, Gratiano; A stage where every man must play a part, And mine a sad one . </P> <P> In his work The Praise of Folly, first printed in 1511, Renaissance humanist Erasmus asks, "For what else is the life of man but a kind of play in which men in various costumes perform until the director motions them off the stage ." </P> <P> Likewise the division of human life into a series of ages was a commonplace of art and literature, which Shakespeare would have expected his audiences to recognize . The number of ages varied: three and four being the most common among ancient writers such as Aristotle . The concept of seven ages derives from medieval philosophy, which constructed groups of seven, as in the seven deadly sins, for theological reasons . The seven ages model dates from the 12th century . King Henry V had a tapestry illustrating the seven ages of man . </P>

When did william shakespeare write all the world's a stage