Īśāvāsyopaniṣat 09, 10, and 11
अन्धन्तमः प्रविशन्ति येऽविद्यामुपासते। ततो भूय इव ते तमो य उ विद्यायां रताः ॥९॥
andhantamaḥ praviśanti ye'vidyāmupāsate। tato bhūya iva te tamo ya u vidyāyāṁ ratāḥ ॥9॥
Those who practice negative-knowledge (negations) enter deep darkness, but those who are engrossed only in positive-knowledge (affirmations) also go to further darkness.
अन्यदेवाऽहुर्विद्यया अन्यदाहुरविद्यया। इति शुश्रुम धीराणां ये नस्तद्विचचक्षिरे ॥१०॥
anyadevā'hurvidyayā anyadāhuravidyayā। iti śuśruma dhīrāṇāṁ ye nastadvicacakṣire ॥10॥
'Positive-knowledge (affirmations) is different from that of negative-knowledge (negations)' - thus we have heard from the wise who do not have distorted insight.
विद्यां चाविद्यां च यस्तद्वेदोभयं सह। अविद्यया मृत्युं तीर्त्वा विद्ययाऽमृतमश्नुते ॥११॥
vidyāṁ cāvidyāṁ ca yastadvedobhayaṁ saha। avidyayā mr̥tyuṁ tīrtvā vidyayā'mr̥tamaśnute ॥11॥
He who knows both the positive-knowledge (affirmations) and negative-knowledge (negations) together, by knowing wrong understanding, crosses over death, and by having right-understanding, attains immortality.
Īśā.Bhāshya 09, 10, and 11
The wise with right insight have both positive-knowledge (affirmations) and also negative-knowledge (negations). Having only one type of knowledge will not lead to the goal. One must overcome fear by negative-knowledge and attain happiness through positive-knowledge.
Those practitioners of different path (with negative-knowledge) go into deep darkness without doubt. But those who take refuge only in positive-knowledge without criticizing (i.e. not having the negative knowledge) enter into even greater darkness.
Therefore, those who know the as-is essence of all pervading lord Narayana, who is without defect, criticizes the improper, knowing them well. Indeed, such people are only righteous. They criticize the improper knowledge in the form of ignorance and suffering.
Having crossed over suffering and ignorance, they attain the state characterized by happiness and knowledge with the help of right knowledge of the reality.
(... states thus in Kaurma Purāna)
Positive Knowledge (vidyā): This refers to knowledge about what something is or what exists. It's the affirmation or assertion of something's existence or qualities. For example, knowing that a particular fruit is an apple or understanding the principles of physics would be considered positive knowledge.
Negative Knowledge (avidyā): Negative knowledge, on the other hand, is knowledge about what something is not or what does not exist. It's the negation or denial of certain qualities or existence of something. For instance, knowing that a particular fruit is not an orange or understanding that a square circle does not exist falls under negative knowledge.
They are often used in philosophical discussions and epistemology to differentiate between affirmations and negations in knowledge. The terms 'vidya' and 'avidya' are used here to mean positive-knowledge and negative-knowledge, and is not used in an ordinary sense to mean knowledge and ignorance. Testimonial quoted from Kaurma Purana further substantiates the same.
