A powerful agent is the right word. Whenever we come upon one of those intensely right words in a book or newspaper the resulting effect is physical as well as spiritual, and electrically prompt.
Wherefore, I beseech you let the dog and the onions and these people of the strange and godless names work out their several salvations from their piteous and wonderful difficulties without help of mine, for indeed their trouble is sufficient as it is, whereas an I tried to help I should but damage their cause the more and yet mayhap not live myself to see the desolation wrought.
Wit and Humor - if any difference, it is in duration - lightning and electric light. Same material, apparently; but one is vivid, and can do damage - the other fools along and enjoys elaboration.
Humor is the great thing, the saving thing after all. The minute it crops up, all our hardnesses yield, all our irritations, and resentments flit away, and a sunny spirit takes their place.