Aprama (अप्रमा)

Not only metaphysical presuppositions are embedded in different theories of valid cognition, even the theories of false cognition which are technically known as 'Khyativada' (Theories of Error) are formulated after keeping parity with such metaphysical presuppositions e.g. when a rope is perceived as snake, it is described as perceived wrongly and reject our earlier cognition as a false cognition. Now the question what is the factor which constitute falsity of the error ? Is the falsity ascribed to the apprehension itself or to both apprehension and content ? These questions are solved by different systems of Indian Philosophy in different ways after following their presupposition. There lies the controversy among different philosophers regarding the nature of false content.

There are six principal theories on such issues called Asatkhyativada, Atmakhyativada, Akhyativada, Anyathakhyativoda, Anirvacaniyakhyativada and Satkhyativada.

The first view - Asatkhyotivada held by the Madhyamikas (Sunyavodins)

of Buddhist school. They maintained that nothing is real in this phenomenal

world. For instance, in the illusory cognition of a shell as a piece of silver is real.

The silver is unreal since it is sublated at the disappearance of the illusion. The

shell is also not real since it is but one factor of the sublating cognition. Others

being the silver and the connection between the silver and the shell. Page 22 of Reference 1

Vaiseshika Aprama

इन्द्रियदोषात्संस्कारदोषाच्चाविद्या । वैशेषिक-९,२.१० ।

तद्दुष्टज्ञानम् । वैशेषिक-९,२.११ ।

Tarkasamgraha

But knowledge is invalid (अयथार्थः । ayatartha) when a character not possessed by the object of cognition is attributed to that object and is called Aprama.

तदभाववति तत्प्रकारकोऽनुभवोऽयथार्थः। यथा शुक्ताविदं रजतमिति। सैव अप्रमा इत्युच्यते॥२०॥ (Tark. Samg. 3.20)

Summary : When a piece of shell is called "this is silver", then the cognition is invalid. For in this case "silverness" is a quality which does not belong to the shell but is being attributed to it is called Aprama.