Chitta – Achitta are two philosophical categories in the Advaita system and Hinduism. Chitta denotes consciousness. Ishwara and the various jivas, animals, birds and other living beings are nothing but the same consciousness conditioned by various adjuncts like intellect, body etc. Thus, the jiva and the paramatman are related in the same way as the vast space and the space conditioned by the pot. However, the theological schools consider Ishwara as a separate third category.
All insentient objects appearing in the world were created by the Absolute through maya. The Absolute, according to the Upanishads, is devoid of any action and parts. Thus, it cannot directly create any object. It creates this multifarious world through the power it has, namely, maya.
Maya is indescribable and acts as a Shakti. It is non-different from the Absolute. It is the material cause of the universe. As maya, which transforms itself into objects, has it locus in the Brahman, Brahman itself is called the cause of several worlds. There was no other thing except Brahman; before the creation of the worlds. Thus, we find that Brahman is both the material and ostensible cause of the worlds.
Cause and effect are related by a very peculiar relationship called non-difference. Though we do not claim identity between them, we cannot also state that they are different totally. We call a pot a mud-pot and a bangle made out of gold a gold bangle. If they are entirely different, we may not call them mud-pot and gold bangle. If they are both identical, then we may be using two synonyms, which is not correct. Hence, cause and effect are non-different.
Thus, we find that in reality consciousness alone remains. All living beings have the same consciousness in them. Their appearance as different beings is due to different adjuncts. All the achitta (insentient objects) are the transformations of maya, which is illusory and hence does not exist really.
This is the basic difference from other systems. Nyaya and Vaiseshika systems too have this classification as chitta and achitta. However, they accept the atomic theory. They state that chitta itself has many subdivisions like Ishwara and jiva. Each body has a distinct jiva. Achitta is both eternal and temporal. Ether, time, directions, and manasa are eternal. The followers of Samkhya, Yoga and Mimamsa too have a similar classification. However, they accept the theory of transformation. All the insentient objects are the result of the transformation on one Mulaprakrit which is real.
Thus chitta and achitta have been understood differently in different systems. In Advaita, achitta is illusory, transforms itself into various objects in the world but has its locus in the Absolute.