Happiness is subjective revenue is objective

Revenue is a measure of objective usefulness to people.

Happiness is a measure of subjective valuing of what we do.

Self-esteem is a measure of subjective usefulness to other people.

Gratitude is a measure of valuing what others do for me.

Let’s bring some formalisation and define a notation:

Revenue equals how others value what I do. Symbolically:

Happiness equals how I value what I do. Symbolically:

Self-esteem equals how I value what I do to others. Symbolically:

Gratitude equals how I value what others to do me. Symbolically:

There are a few observations: