A fundamental Advaita doctrine, Ajativada was first expounded in Gaudapada’s Mandukya Karika. It has two sub-doctrines. The first doctrine says that atman (the self) is aja (unborn) ad according to the second, creation is an illusion in the sense of being a construct.
Gaudapada contends that duality is a mere appearance, and non-duality is the absolute truth. Ajativada does not accept the concept of causality and hence proves that creation is an impossibility. Gaudapada puts forward the following arguments:
Nothing is born out of itself or out of another or out of both together (Mandukya Karika 4.22. a. b). A pot cannot come of itself, nor can it be produced out of a piece of cloth.
Though a pot appears to be produced from clay or a son born to a father it is not so in reality. Nothing, in fact, is produced whether it is existent or non-existent or both together (Mandukya Karika 4.22. c. d). If a thing is existent, it cannot be produced, for it is already there. Nor, the third, i.e. that it is both existent as well as non-existent, for this involves a contradiction.
The concept of causality is not tenable because the non-existent cannot have the non-existent for its cause, as the horns of a hare cannot be the cause of a castle in the air; nor can the existent have the non-existent for its cause, as the horns of a hare cannot be the effect of the existent, because the existent already exists. If it exists already, it does not need a cause, as a chair cannot be the cause of a jar; again, the existent cannot be the effect of the non-existent, for that which does not exist cannot produce anything (Mandukya Karika 4.38.40).
Ajativada also shows that other theories of causation do not stand to reason. According to Satkaryavada (principle which states that result inheres in the cause) of the Samkhya Yoga school of thought, the origination of a thing is already existent in its cause while the Astakaryavada (principle which states that the result does not inhere in the cause and it depends on the karta (agent) of Nyaya Vaisheshika school maintains that everything is independent of a cause (Mandukya Karika 4.3). In this way, both contradict one another and prove Ajativada (Mandukya Karika 4.4).
Further, Satkaryavada attributes birth to something which is unborn but must be immortal. To say that unborn is born is to attribute mortality to it. The immortal cannot become moral, nor vice versa, for it is impossible for a thing to change its nature. (Mandukya Karika 4.6).
Asatkaryavada cannot be proved since nothing could be produced out of non-existence. Ajativada refutes the theory of dependent origin of Buddhism on the ground that simultaneity between cause and effect is not possible. Ajativada also maintained that the common notion of causality is based on the concept of time as a real entity. But when time is analyzed without any relation to space and direction, the notion of causality becomes meaningless.