In Hindu religion, ajnana is lack of knowledge or conditioned knowledge. According to Vedanta philosophy, Brahman (the Supreme Being) is one without a parallel. It is attributeless and can be understood as the nature of sat (existence), chit (consciousness) and ananda (bliss). It alone is real and all other constructs are avidya (un-differentiated consciousness).
Ajnana leads one into believing that the impermanent is permanent. Vedanta philosophy expounds that anitya (transient) cannot be considered nitya (permanent), as it is bound to come to an end. Getting attached to one’s body and senses due to ajnana is called dehabuddhi (physical consciousness).
An ordinary human being is unable to differentiate between the self and the body. If one has clear conception of the non-transitory nature of atman (the self), he will realize that the body is, merely, a vehicle inhabited by the self. The body has a beginning and an end, while the self has neither a beginning nor an end. But due to ajnana, one usually gets attached to the body and other material objects and tries to conserve them. One is thus unable to distinguish the real from the unreal.
Vedantins use the term avidya, ajnana and prakriti (matter or primordial nature) to explain the misconception of comprehending reality as one made up of matter devoid of the Self. Under the influence of ajnana, atman or pure consciousness appears as the jiva (the experiencing self), the Absolute appears as the relative and/or the One asmany. The word prakriti is used for matter and maya for the power that shapes our universe out of the primordial matter. The word maya has, however, been misconstrued in the English translations of and the commentaries on, the primary Vedic texts as a cosmic illusion.
Maya in the Rig Veda denotes a constructive power. It is mentioned that Indra, through the help of maya assumed different forms (Rig Veda 1.11.7). In the Upanishads, the concept is elaborated to denote the role of consciousness in the construction of reality. In the Bhagavad Gita, Sri Krishna exhorts Arjuna to pass beyond this material world, a construct of maya, by taking refuge in Him, the Universal Self (Srimad Bhagavad Gita 7.14).
Ajnana as constructive power has two dimensions – avarana shakti (power to cover something) and vikshepa shakti (power to transform). One is the veiling power and the second is the transforming power. It is the power of ajnana that causes atman (the self) to appear, to be veiled, as many jivas and therefore it is maya that causes the world of phenomena. This awareness enables the seeker to differentiate between the real and the unreal.