UGCNET Questions

A viruddha hetu is one whose accepted vyāpti actually yields the negation of the thesis. When the hetu is combined with its known universal relation, it logically supports the opposite conclusion. This makes the argument self defeating, as the reason undermines rather than backs the stated sādhya. Hence viruddha is considered one of the gravest logical defects in Indian logic.

Option A:
Option A describes an asiddha hetu, where the reason is not established in the subject, but viruddha assumes the hetu and its vyāpti are accepted.

Option B:
Option B correctly states that a viruddha hetu ends up proving the opposite of what the arguer wants, so its acceptance forces rejection of the thesis.

Option C:
Option C characterises an irregular or anaikāntika hetu, which may be too broad but does not necessarily reverse the conclusion.

Option D:
Option D focuses on scriptural basis; a scriptural statement could form part of a valid or invalid hetu, but being scriptural does not by itself create the viruddha defect.

A viruddha hetu is one whose accepted vyāpti actually leads to a conclusion contrary to what the reasoner wants to prove. Instead of supporting the intended sādhya, the middle term supports its negation. This makes the inference self defeating, because if the hetu is accepted, the conclusion must be the opposite of the stated thesis. Such a reason is deeply defective, as it undermines the very claim it is meant to justify.

Option A:
Option A characterises an asiddha hetu, where the middle term is not established in the pakṣa; this is a different kind of fallacy.

Option B:
Option B mentions over narrowness but does not capture the central feature of viruddha, namely reversing the intended conclusion.

Option C:
Option C correctly identifies that a viruddha hetu proves the contrary of the thesis on the basis of its own vyāpti, making the argument logically self destructive.

Option D:
Option D focuses only on the source of evidence; dependence on scripture is not, by itself, what defines viruddha in technical classifications of hetvābhāsa.