The Advaita Vedānta philosophy is generally known as śāntabrahmavāda or Kevalādvaita. The philosophy of Kashmir is known as īśvarādvayavāda or Pratyabhijñā or Trika.
The Nature of Absolute Reality
The most salient difference between the two is that according to Vedānta, the Absolute Reality is simply Prakāśa or jñāna, whereas according to īśvarādvayavāda, it is Prakāśa-vimarśamaya, i.e., it has both jñātṛtva and kartṛtva. Shankaracharya thinks that kriyā or activity belongs only to jīva or the empirical individual, and not to Brahman. Shankara takes kriyā in a very narrow sense. He takes it as synonymous with karma. Certainly, Paramaśiva does not act like a potter molding clay into pots. śaivāgama takes kriyā in a wider sense, in the sense of citśakti, in the sense of Spanda, throb or pulsation to manifest.
Without activity, the Absolute would be simply inert, unable to bring about anything.
Shankara says: ‘All activity belongs to Māyā.’ But is Māyā simply a śakti of Brahman or is it something quite external’ If Māyā is something quite external, then Advaita cannot be maintained. If Māyā is śakti of Brahman, then surely, it is an activity of Brahman.
According to śaivāgama, svātantrya or autonomous Free Will is an important characteristic of Chaitanya. Kartṛtva is an important aspect of svātantrya. As Pāṇini puts it: svatantraḥ kartā, a free being alone is an agent. Svātantrya of śiva implies kartṛtva.
According to Advaita Vedānta, Brahman is entirely inactive. Activity belongs to avidyā. When Brahman is associated with avidyā, it becomes īśvara who is endowed with the power to act. So the real activity belongs to avidyā. The activity of īśvara ceases when He is dissociated from avidyā. This is what Shankara says in his commentary on Brahmasūtra:
‘Thus the potency of īśvara, His omniscience and omnipotence are contingent upon the limitation caused by the condition or association of avidyā (primal ignorance). In the highest sense, when all conditions are removed by vidyā (spiritual illumination) from the ātmā, the use of potency, omniscience etc., would become inappropriate for it.’ (2.1.14)
On the other hand, jñātṛtva and kartṛtva are, according to īśvarādvayavāda, the very nature of the Supreme. Activity, according to this philosophy, is not an adjunct of īśvara, but His specific nature. His activity is summed up in the fivefold act of sṛṣṭi (manifestation), sthiti (maintenance), saṃhāra (withdrawal), vilaya (concealment of real nature) and anugraha (grace). He performs these five acts eternally even when He assumes the form of an empirical ego (jīva).
Maheśvarānanda says in his Mahārthamañjarī that inactive Brahman is as good as unreal.
‘This is the specific nature of Parameśvara that He always performs the fivefold act of sṛṣṭi etc. If this is not accepted, ātmā as defined by Māyāvāda characterized by the want of the slightest trace of activity, would be as good as unreal.’
According to Shankara, Brahman is entirely inactive; all activity is due to Māyā. According to īśvarādvayavāda, activity belongs to śiva or īśvara; Māyā derives its activity only from Him.
Secondly, Māyā according to Advaita Vedanta is anirvacanīya or indefinable, but according to īśvarādvayavāda, Māyā being the śakti of śiva is perfectly real and brings about multiplicity or difference.
śvetāśvarata Upaniṣad equates Māyā with Prakṛti:
māyāṃ tu prakṛtiṃ vidyānmāyinaṃ tu maheśvaram |
The word Māyā is derived from the root ‘mā’ which means ‘to measure’. Māyā is that power of the Divine which measures out the phenomenon in definite forms. Māyā is the creative power of the Divine and not a power of illusion.
The Status of the World
The world, according to Shankara, is mithyā or false. It is simply an adhyāropa or adhyāsa or false imposition on Brahman due to ajñāna or nescience just as a snake is a false imposition on a rope.
In none of the Upaniṣads which form the original and real Vedānta, the rajju-sarpa or rope-snake analogy is to be found. Nor anywhere in the Upaniṣads has the world been designated as adhyāropa or adhyāsa. Shankara has borrowed it from Nāgārjuna.
The problem for Advaita is: ‘How does the one Brahman become many” Sri Aurobindo rightly says that Shankara cut the Gordian knot by dismissing the world as illusion. Mahāmahopādhyāya Dr. Gopinath Kaviraj says that according to adhyāsa, Shankara’s Advaita becomes exclusive advaita, an advaita by excluding the world.
For Advaita śaivāgama, the world is an ābhāsa, but ābhāsa or appearance is real. The ābhāsas only prove the glory and richness of śiva. The world lies only as a potency in śiva, just as a banyan tree lies as potency or śakti in the seed. Manifestation only means making explicit what is implicit. Variety is not contradictory to unity. Advaita śaivāgama maintains that Pariṇāmavāda and Vivartavāda are not the exhaustive theories of manifestation. Manifestation is brought about by the svātantrya or the autonomy of śiva.
The Role of Anugraha or Grace
According to śaivāgama, Anugraha or Grace is one of the eternal activities of śiva.
The Upaniṣads which constitute the actual Vedānta also believe in Anugraha. Kaṭhopaniṣad explicitly states:
‘This ātmā cannot be attained by instruction, not by intelligence, nor by learning. To him alone, It reveals Its subtle form whom It chooses.’
This stanza plainly speaks of Grace, but Shankara dismisses grace by a linguistic tour de force. He takes ‘eṣa’ as standing for ‘sādhaka’, though it is a pronoun standing for the noun ātmā.
In another place, curiously enough, Shankara admits Grace. Commenting on the Brahmasūtra (3.2.5), he says:
‘Just as when the power of sight withdrawn owing to cataract is restored with the potency of medicine, even so only to some rare being whose spiritual darkness has been removed by the discipline of meditation, and who has attained fulfillment through the grace of God is Realization restored. It does not come by itself.’
The word ‘īśvaraprasāda’ shows clearly that Shankara has admitted the grace of God in this context.
ātmā in the Human Body
According to Shankara, ātmā in the human body is only sākṣi-caitanya or witnessing consciousness. Just as Brahman as no activity, even so, its reflection ātmā in the human body is niṣkriya – without activity. According to īśvarādvayavāda, however, ātmā in the human body also is spandamaya. It has always the characteristic of jñāna and kriyā.
Difference in the Upāyas
śaivāgama has four upāyas: anupāya, śāmbhavopāya, śāktopāya and āṇavopāya. According to Vedānta, śravana, manana and nidhidhyāsana are the only means to liberation. This partially represents the śāktopāya of śaivāgama. There is nothing like śāmbhavopāya or āṇavopāya in Vedānta.
Difference in the Conception of Ajñāna
According to Vedānta, avidyā or ajñāna is removed by vidyā or jñāna, and when this happens, there is mukti or liberation.
According to śaivāgama, there are two kinds of ajñāna: bauddha and pauruṣa. Bauddha ajñāna is intellectual. By vidyā, only bauddha ajñāna can be removed, pauruṣa a~jnāna will still remain. Such a person will only be landed in blank abstraction. He will not realize śivatva.
Pauruṣa ajñāna also has to be removed. This can be removed by śaktipāta which comes about either by dīkṣā by a Self-realized Guru or by direct divine grace.
Difference in the Conception of Liberation
The idea of mukti in Vedānta is Kaivalya or isolation just as in Sāṃkhya-Yoga. The only difference is that in Sāṃkhya-Yoga, it is isolation from Prakṛti, in Vedānta, it is isolation from Māyā. The ideal of Mukti in śaivāgama is śivatva yojanā or being integrated to śiva.
According to Vedānta, the world is annulled in Mukti. According to śaivāgama, the world appears to be a form of śiva-consciousness in liberation.