As men had no capacity to study the entire Veda, it came to be divided into several parts. And as the intellect (of men) deteriorated, few were devoted to truth.
एकवेदस्य चाज्ञानाद् वेदास्ते बहवः कृताः। सत्त्वस्य चेह विभ्रंशात् सत्ये कश्चिदवस्थितः॥