If you see someone without a smile, give them one of yours. If you see someone without a sense of humor, RUN!
“The hypothetical person lacking a sense of humour would likely find the behaviour induced by humour to be inexplicable, strange, or even irrational. Though ultimately decided by personal taste, the extent to which a person will find something humorous depends upon a host of variables, including geographical location, culture, maturity, level of education, intelligence and context.” — (wikipedia)
“Humor can be dissected as a frog can, but the thing dies in the process and the innards are discouraging to any but the pure scientific mind.” — E.B. White