यद्यदाचरति श्रेष्ठस्तत्तदेवेतरो जनः। स यत्प्रमाणं कुरुते लोकस्तदनुवर्तते।।3.21।।
yad yad ācharati śhreṣhṭhas tat tad evetaro janaḥ sa yat pramāṇaṁ kurute lokas tad anuvartate
yat yat—whatever; ācharati—does; śhreṣhṭhaḥ—the best; tat tat—that (alone); eva—certainly; itaraḥ—common; janaḥ—people; saḥ—they; yat—whichever; pramāṇam—standard; kurute—perform; lokaḥ—world; tat—that; anuvartate—pursues
Whatever a great man does, others also do; whatever he establishes as the standard, the world follows.
3.21 यद्यत् whatsoever? आचरति does? श्रेष्ठः the best? तत्तत् that? एव only? इतरः the other? जनः people? सः he (that great man)? यत् what? प्रमाणम् standard (authority? demonstration)? कुरुते does? लोकः the world (people)? तत् that? अनुवर्तते follows.Commentary Man is a social animal. He is an imitating animal too. He takes his ideas of right and wrong from those whom he regards as his moral superior.
Whatever a great man follows? the same is considered as an authority by his followers. They try to follow him. They endeavour to walk in his footsteps.