Happiness is the relative sense which varies according to individual abilities, potentials and motivations. It is a spiritual embodiment of a joyful reality.
In philosophy, happiness is translated from the Greek concept of eudaimonia, and refers to the good life, or flourishing, as opposed to an emotion.
In psychology, happiness is a mental or emotional state of well-being which can be defined by, among others, positive or pleasant emotions ranging from contentment to intense joy.[1] Happy mental states may reflect judgements by a person about their overall well-being.
Scientific research is a fun thing. Everything can be measured and evaluated. For me happiness is a state of mind, feeling, I feel it and do not measure it.
I partially agree with Piotr Bętkowski that we cant exactly measure happiness. but we can even then classify on a scale from 1 to 5, where 1 could be slightly happy to extremely happy. So that how even we can measure modes. Such technique are very commonly applied in social sciences.
Happiness can be measured in different ways. To me, the evaluation my personal encounters and whether they have positively affected others can bring to me a clear conscience and a good night sleep . In point of fact, a clear conscience can be regarded as a fair estimation of happiness. By loving and caring for others, we build a condition which is essential to our own happiness.