But continuing, Jonson is careful to add: 

    “But that a rook by wearing a pied feather,
    The cable hat-band, or the three-piled ruff,
    A yard of shoe-tie, or the Switzers knot
    On his French garters, should affect a humour! 
    O, it is more than most ridiculous.”

Jonson’s comedy of humours, in a word, conceived of stage personages on the basis of a ruling trait or passion (a notable simplification of actual life be it observed in passing); and, placing these typified traits in juxtaposition in their conflict and contrast, struck the spark of comedy.  Downright, as his name indicates, is “a plain squire”; Bobadill’s humour is that of the braggart who is incidentally, and with delightfully comic effect, a coward; Brainworm’s humour is the finding out of things to the end of fooling everybody:  of course he is fooled in the end himself.  But it was not Jonson’s theories alone that made the success of “Every Man in His Humour.”  The play is admirably written and each character is vividly conceived, and with a firm touch based on observation of the men of the London of the day.  Jonson was neither in this, his first great comedy (nor in any other play that he wrote), a supine classicist, urging that English drama return to a slavish adherence to classical conditions.  He says as to the laws of the old comedy (meaning by “laws,” such matters as the unities of time and place and the use of chorus):  “I see not then, but we should enjoy the same licence, or free power to illustrate and heighten our invention as they [the ancients] did; and not be tied to those strict and regular forms which the niceness of a few, who are nothing but form, would thrust upon us.”  “Every Man in His Humour” is written in prose, a novel practice which Jonson had of his predecessor in comedy, John Lyly.  Even the word “humour” seems to have been employed in the Jonsonian sense by Chapman before Jonson’s use of it.  Indeed, the comedy of humours itself is only a heightened variety of the comedy of manners which represents life, viewed at a satirical angle, and is the oldest and most persistent species of comedy in the language.  None the less, Jonson’s comedy merited its immediate success and marked out a definite course in which comedy long continued to run.  To mention only Shakespeare’s Falstaff and his rout, Bardolph, Pistol, Dame Quickly, and the rest, whether in “Henry iv.” or in “The Merry Wives of Windsor,” all are conceived in the spirit of humours.  So are the captains, Welsh, Scotch, and Irish of “Henry V.,” and Malvolio especially later; though Shakespeare never employed the method of humours for an important personage.  It was not Jonson’s fault that many of his successors did precisely the thing that he had reprobated, that is, degrade “the humour:  into an oddity of speech, an eccentricity of manner, of dress, or cut of beard.  There was an anonymous play called “Every Woman in Her Humour.”  Chapman wrote “A Humourous Day’s Mirth,” Day, “Humour Out of Breath,” Fletcher later, “The Humourous Lieutenant,” and Jonson, besides “Every Man Out of His Humour,” returned to the title in closing the cycle of his comedies in “The Magnetic Lady or Humours Reconciled.”