There is a tremendous quote attributed to the late, great author and poet Maya Angelou, which declares "I've learned that you can tell a lot about a person by the way he/she handles these three things: a rainy day, lost luggage, and tangled Christmas tree lights."
I like these three random items a lot, they provide a handy and instant happiness litmus test as to our general happiness set point - are we a glass half full or a glass half empty kind of person?
Happiness is a temporal sensation and, if we want to feel happy more often, we have to keep finding reasons to keep happiness present and not get knocked off course by the inevitable small stuff that comprises a life.
Some people will find that the small stuff not going as expected will derail their entire day. Others can seem to deal with the bad thing but press the reset button after it's done, and keep seeking things to feel good about as they move through the rest of their day. They stop the downward spiral into a bad day before it even starts.
Knowing what our habitual patterns are, and whether they serve us, is so powerful, which is why these three ordinary happenstances are such a great check: