Ethical excellence is very essential and it is not recognized as it should be, that ethical excellence is the very foundation of spiritual life. The Sankha, the Yogurt and the Vedanta insists on this a lot. So when Patanjali also begin to deal with Supra mental existence and its achievement, he begins with Yama and Niyama. As we know that these two are the initial two limbs of Ashtang yoga. So there are many sutras based on these