Happiness is a natural response to being grateful.

Write a thank-you note to someone and check your own mood twenty minutes later. Something has shifted, and it has nothing to do with whether they have read it yet.

The order runs backwards from what people expect. Most wait to feel good and then feel grateful. In practice the gratitude goes first and drags the mood along behind it, slightly reluctantly. Which is why it still works on bad days. You do not have to feel anything in order to name three things that went right.

The feeling arrives late, like a friend who never texts to say they have left the house.