The proof of this, i.e. the difficulty of ascertaining one's caste is found in such expressions, made use of by the Rishis, as *whatever caste may belong to, we celebrate the sacrifice." It is, on this account, that the wise have asserted that the character is the chief and needful thing.
इदमाएं प्रमाणं च ये यजामह इत्यपि। तस्माच्छीलं प्रधानेष्टं विदुर्ये तत्त्वदर्शिनः॥