Psychology is a means by which unhappiness is overcome and satisfaction, happiness, nirvana and parinirvana attained.

How is psychology a means by which unhappiness is overcome?

Psychology is the study of the self.

And it is through the study of the self that unhappiness is overcome and satisfaction, happiness, nirvana and parinirvana attained.

Through the study of psychology one grows in knowledge of the self.

And through growth in knowledge of the self one's self grows.

And through growth in knowledge of the self one grows to overcome unhappiness and attain satisfaction, happiness, nirvana and parinirvana.