Avidya is that portion of the primitive non-intelligent principle in which Sattva is subordinated to Rajas and Tamas. This is known as Malina Sattva, because it is impure on account of the predominance of Rajas and Tamas. It is the reflector of Jiva whereas Maya is the reflector of Isvara. Maya is called Suddha Sattva on account of the predominance of Sattva. This world of experience is due to the force of Avidya. It is the force of Avidya that plunges us into the ocean of Samsara. It is a negative power which makes us forget our divine nature. Avidya operates through the mind, and the mind functions through the time, space and causation. Avidya is an illusory power that disintegrates the Divine into a million different fragments. Pleasure, pain, desire, Karma, attraction, repulsion, delusion, pride, lust, egoism, anger, jealousy, the three bodies, five sheaths, are all effects of Avidya. Avidya is the source of all ignorance, sin and misery. Avidya is beginningless (Anadi) but it has an end.
As soon as one gets knowledge of the Self, Avidya terminates. Brahman appears as the world on account of Avidya, just as the rope appears as snake in the dusk. If we bring a lamp, the snake disappears, but the rope alone remains. Even so, when we get knowledge of Brahman, the appearance of the world will vanish. Avidya is not negative, but is positive (Bhavarupa). It is absence of Knowledge. It is erroneous knowledge. Avidya or Ajnana which constitutes the causal body is the cause for the two bodies, gross and subtle.
It is impossible to define the nature of Avidya. It is Anirvachaniya. It is not real, because it vanishes when knowledge of the Self dawns. It is not unreal, because we experience it unlike the horn of a hare or a barren woman's son. It is not a non-entity as it is destroyed by Atma Jnana. It is through the force of Avidya that the ignorant Jiva has mistaken the impure mortal body for the pure immortal Self and says I am a Brahmin, I am a Pandit, I am a householder, I am beautiful, I am lean, I am a doctor, etc.
No explanation is possible for the rise of this deluding Avidya. This has somehow come into phenomenal being. Although its origin and explanation are beyond our reach, its operation through the mental categories is clearly perceptible. The Avidya cannot be the Brahman's because He is an embodiment of pure knowledge. How can there be darkness in the sun? It cannot belong to the souls, as they are not distinct from the Brahman. If Avidya were an essential property of the Atman, he could never get rid of it.
Anyhow you are caught up within the clutches of Avidya. Do not rack your brain with the question: Whence comes Avidya? Kim Bhranti Jnanam? Yadi Bhranti Sa Kasya? Whose is Avidya? Why should there be Avidya? Try to get out of this fire of Samsara or this ocean of darkness. This is your duty. There are two ways to cross this ocean of Samsara. These are clearly chalked out by Rishis and Sages of yore. When you have attained knowledge of the Self, you will have a clear understanding of the nature, why and how of the formidable Avidya. Will a patient who is suffering from severe abdominal colic try to enquire from his friend when he gets some medicine, Where from did you get this medicine? What are its components? What is the price? Who gave the medicines? Will he not swallow it immediately? Will a man whose cloth is caught in fire run towards water immediately to cool himself or will he be philosophising How did this fire come? etc.