When we are divorced from spiritual cultivation, from understanding that the purpose of life is God realization and not sense gratification, then we will think, “Why shouldn’t we do whatever we like as long as it doesn’t harm others?” But they don’t know that we are harming ourselves by such a mentality, because: na te viduh svartha-gatim hi visnum, our real self interest is to understand Krishna; and any activity performed without this in mind is apasvartha, or that which is not actually in our self interest.
Lecture on SB 3.6.32 – About the Four Varnas – Vyasa Puja 2008 – 5th Jan'08 – Tirupati