베다에서 성찰한 인격의 세 층위 중 aja는 베단타의 자아 개념과 더욱 부합하고, tanū는 상키야의 미세신과 더욱 부합한다고 말할 수 있다. 이에 따라 베단타의 일원론에서는 영혼 개념에 물질성을 전혀 고려하지 않지만, 상키야의 이원론에서는 여기에 물질성을 고려한다. 그러나 자아에 관한 베단타와 상키야의 인식이 현저하게 다르다고는 말할 수 없다. 양측의 차이는 반영설에 의해 인식론 차원에서 희석될 수 있기 때문이다. 즉 반영설에 의해 베단타의 자아(Ātman)는 개아(영혼)인 양 활동할 수 있으며, 상키야에서 개아에 상당하는 Buddhi는 자아(Puruṣa)인 양 인식할 수 있다.
결국 베단타와 상키야 사이의 공유 관념으로 확연히 드러나는 것은 Buddhi이다. 이 Buddhi는 양측에서 활동성의 의식인 개체적 사이비 자아를 대변한다. 영혼의 역할을 담당하는 주체도 이것이며, 인식아와 내아와 명아 등도 이것의 별칭으로 간주할 수 있다. 여기서 자아와 영혼은 의식의 비활동성과 활동성으로 차별되므로 윤회(활동)하지 않는 영혼이 자아라면, 윤회(활동)하는 자아는 영혼이다.
한편 상키야의 미세신은 자아 개념에 관한 한 베단타와 차별할 수 있는 관념을 대변한다. 그러나 베단타 불이일원론을 적용하면, 미세신도 무지의 소산이요 자아의 upādhi일 뿐이다. 베단타에서 해탈은 이 upādhi를 자아로 착각하는 무지에서 벗어남으로써 실현된다. 상키야의 경우에는 Buddhi를 자아로 착각하는 무지에서 벗어남으로써 Puruṣa의 독존이라는 해탈을 실현한다. 베단타든 상키야든 해탈의 논리는 동일하다. 양측의 차별적 관념은 동일한 해탈의 논리로 회귀한다고 말할 수 있다. 그러므로 차별 관념이 아무리 격렬할지라도 그 이면의 공유 관념으로 진화(鎭火)될 수 있는 것이 인도 철학의 자아 개념일 것이다.
The refection on the ‘I’ from the ancient time in Indian philosophy is just a quest of the self. Speaking in a broad way, it is also a part of reflecting on and investigating human personality. It’s origin may be traced in the Veda as aja, tanū, and śarīra, which are three constituents of human personality connected closely with Upaniṣadic speculations in a later period. Of these we are inclined to attach weight to aja and tanū as the preceding notions corresponding to the self and the soul respectively.
Aja corresponds to Ātman identified with Brahman. By the way, this aja together with ajā, or the feminine of aja described in Upaniṣads are also regarded as scriptural authorities in support of Sāṃkhya dualism. In this case, Puruṣa is compared to aja, and Prakṛti is compared to ajā. Therefore aja is a constituent of human personality corresponding to the predecessor of the self called Ātman or Puruṣa.
Meanwhile, according to the Veda, the subtle structural unit which carries the mental faculties of the personality is called tanū. Moreover tanū is characterized as what is restored to man when he has died and his physical body has been burnt and his personality dissolved. Thus it accords with the so-called soul, and also we can consider it as the notion corresponding to the predecessor of jīva, or the individual self. Besides, to the extent that tanū is the subtle structural unit which carries the mental faculties of the personality, it may also be the predecessor of the transporting(ātivāhika) or subtle(sūkṣma) body which is held by Sāṃkhya.
Lastly, śarīra is what is composed of the five gross elements, and refers to the body which is the visible and tangible physiological organism.
Of three layers of human personality as above, we may say that aja tallies further with the self of Vedāntic notions and tanū tallies further with the subtle body of Sāṃkhya notions. While in the case of the monism of Vedānta materiality is not in consideration at all about the notion of the soul, in the case of the dualism of Sāṃkhya the notion of the soul which belongs to the categories of materiality is taken into consideration.
However, we cannot say that the cognition relating to the self between Vedānta and Sāṃkhya is different remarkably. Though the difference of both is caused by each ontology between Vedānta and Sāṃkhya, it also can be weaken by the theory of reflection at the level of epistemology. In other words, the self of Vedānta can acts as if it were an individual self, and Buddhi of Sāṃkhya can cognizes as if it were Puruṣa. This is possible through the theory of reflection.
After all, what reveals itself definitely as a common idea between Vedānta and Sāṃkhya is just Buddhi. The individual pseudo-self is represented in both sides by that Buddhi which is the consciousness of activity. The Buddhi is not only the knowing subject which serves as the soul, but also can be called as another names, that is to say vijñānātman, antarātman, jīvātman, and so on.
Meanwhile, as far as the notion of the self is concerned, the subtle body of Sāṃkhya is a typical idea to be differentiated from Vedānta. But based on the advaita of Śaṅkara, the subtle body is nothing but the result of ignorance(avidyā), and it is only upādhi of the self.
Ātman identified with Brahman, namely a state of liberation in Vedānta, is realized by being free from ignorance mistaking the upādhis for the self. The isolation of Puruṣa, namely a state of liberation in Sāṃkhya, is realized by being free from ignorance mistaking the Buddhi which leads the subtle body for the self. The logic for liberation held in whether Vedānta or Sāṃkhya is the same. We can say that the different ideas between Vedānta and Sāṃkhya revert back into the same logic for liberation.
Accordingly, however vehemently the different ideas have been discussed, what can be weaken by the common ideas behind them would be the notion of the self in Indian philosophy.
