Society is defined as an aggregate group of people living together within a community.
Since, a society is composed of people, its welfare is dependent on the well-being of its components, the people.
Well being of an individual is manifested through his or her good condition of existence; health, happiness, and prosperity.
A society filled with people who are healthy, happy, and prosperous will also have a positive welfare.
Welfare of my society depends on my well being, my well being will also be affected by the welfare of my society.