Note 81 — ACT I.
Reading edition
That is, act from caprice. So in Ben Jonson's "Every Man out of his Humour," induction: "When you come to plays, be humorous, look with a good starch'd face, and ruffle your brow like a new boot; laugh at nothing but your own jests, or else as the noblemen laugh." Again, in Decker's "Satiromastix," 1602—
"All our understanding faculties Sit there in their high court of parliament, Enacting laws to sway this humorous world, This little isle of man."
And in the "Second Part of King Henry IV.," iv. 4, we have—
"Being incens'd, he's flint, As humorous as winter" ——
See also Mr Steevens's note on the last passage.