Doing good only to good people leads to happiness

उपकारो हि साधूनां सुखाय किल संमतः |

उपकारो ह्यसाधूनामपकाराय केवलम् || 45 ||

 

It is generally agreed that doing good to good people leads to happiness. Doing good to bad people (is possible) only by doing harm/offence.