precludes having a sense of humor.? Optimism or positive thinking requires a person to be insanely upbeat to the point of not even allowing negative thoughts to enter their mind. There's no way anyone can be an unbridled optimist and have a sense of humor because humor is based on human frailty. People who are amusingly offbeat make much better company than cockeyed optimists who are deadly dull automatons. Thoughts on this?