In Commedies, the greatest Skyll is this, rightly to touche
All thynges to the quicke: and eke to frame eche person so,
That by his common talke, you may his nature rightly know:
A Royster ought not preache, that were to straunge to heare,
But as from vertue he doth swerve, so ought his woordes appeare:
The olde man is sober, the yonge man rashe, the Lover triumphyng in ioyes,
The Matron grave, the Harlot wilde and full of wanton toyes.
[Prologue, 14-20]
George Whetstone seconds this propriety in his Epistle to William Fleetwood, prefixed to Promos and Cassandra:
For to worke a Commedie kindly, grave olde men, should instruct: yonge men, should showe the imperfections of youth: Strumpets should be lascivious: Boyes unhappy: and Clownes, should be disorderlye.