It is a logical truism that everything we do, we do it for the sake of “our own” happiness (despite What Bryan Adams would have us believe – Everything I Do, I Do It For You – https://www.youtube.com/watch?v=Y0pdQU87dc8) because we would never want to do anything that cause us pain or unhappiness.
At the same time, it would also seem true that it matters a great deal whether seek “our own” happiness by “doing” everything for ourselves or we do at least somethings for the sake of others because it is a well-researched and proven fact that we do derive a great deal of joy and happiness by “doing” things for the sake of others (https://selfrealization.blog/2025/10/24/simple-route-to-happiness/) – think of all your relationships in your life you have had so far, be that relationship with parents, siblings, relatives, friends, colleagues, etc., where you surely must have done something for their sake without explicit regard to your own self-interest except insofar as it might have contributed indirectly to “your own” happiness.
That is why perhaps, Gurujada Appa Rao, wrote, “Sontha labham kontha manuko, porugu vadiki thodu padavoyi”.
Also, look up:
Rational Fools
by Amartya Sen
“In his Mathematical Psychics, published in 1881, Edgeworth asserted that “the first principle of Economics is that every agent is actuated only by self-interest.” This view of man has been a persistent one in economic models, and the nature of economic theory seems to have been much influenced by this basic premise. In this essay I would like to examine some of the problems that have arisen from this conception of human beings.”
Know Thyself 