“I use the term happiness to refer to the experience of joy, contentment, or positive well-being, combined with a sense that one's life is good, meaningful, and worthwhile.”

Why it was said

Early in The How of Happiness, before she describes a single practice, Sonja Lyubomirsky stops to define the word the whole book is about. Her definition joins two strands that researchers often measure separately: how a person feels from day to day, and how they judge their life as a whole.

What it actually means

The definition has two halves, and both matter. Joy, contentment and positive wellbeing describe how days feel. A sense that life is good, meaningful and worthwhile describes a judgement about the whole. A person can have plenty of the first and little of the second, or the reverse: a demanding season caring for a parent can feel hard and still be deeply meaningful. By naming both, Lyubomirsky sets the bar for her practices: they should improve how life feels and how it adds up, not just produce pleasant moments.

How to use it

1. 1When you check whether a practice is working, ask both questions: are my days lighter, and does my life feel more worthwhile?
2. 2In a hard week, look for the second half; meaning can be present when contentment is not.