Since WHO’s definition of health is, “physical, mental, and social well-being, not merely the absence of illnesses”, then mental health is the "mental" part in this definition, that is, it is mental well-being, not just absence of mental illnesses.
That reminds us we want to approach it more from the positive/well-being side, and this is one of the efforts of my approach:
Both, but I emphasize more on the latter as it is less aware and emphasized: Happiness is a contributing factor for mental well-being, proven by modern sciences, including my own research.
Since WHO’s definition of health is, “physical, mental, and social well-being, not merely the absence of illnesses”, then mental health is the "mental" part in this definition, that is, it is mental well-being, not just absence of mental illnesses.
That reminds us we want to approach it more from the positive/well-being side, and this is one of the efforts of my approach:
https://drjaneforhappiness.substack.com/p/how-important-is-happiness-for-mental?r=31zx1q
Fascinating work Dr. Xu - will read in more detail.
Is happiness a measure or a contributing factor? Or both?
Both, but I emphasize more on the latter as it is less aware and emphasized: Happiness is a contributing factor for mental well-being, proven by modern sciences, including my own research.
I'll do some further reading - as I'm always keen to learn about evidence backed work in this space. Thanks for bringing it to my attention.