Though it is self-luminous, it is categorised as acetana or non-sentient, as distinct from Ishwara and jiva, which are cetanas or sentient beings. This is a peculiar classification adopted by the Visistadvaita Vedanta. Cetana, in this system means that which is a substrate or subject of knowledge (chaitanya visista). Knowledge (jnana) as well as nitya vibhuti taken as a dravya,(substance) are acetanas because they are not the subjects of knowledge. That is, they only reveal the objects like light but they do not know the objects thus revealed as in the case of jivas because they do not possess knowledge as a quality.
This leads to the question whether what is acetana or non-sentient can be self-luminous (svayamprakasatva). The answer to this lies in the affirmative. According to the Visistadvaita epistemology, the function of knowledge is to reveal something and while it reveals, it does not require the aid of another knowledge to reveal it. This is the meaning of svayamprakasatva or self-luminosity. However it is not jada or an inert object, in which case it would not be able to reveal the objects. Svayamprakasatva and ajadatva (spirituality) are not opposed to each other. Jnana and nitya vibhuti are regarded as self-luminous in order to bring out the fact that they are not material but are essentially spiritual in character.
Even among the Visistadvaitins, some have taken the view that suddhasattva is jada or material and not spiritual in character. The reason for holding this view is that in some Pancharatra treatises the nitya vibhuti and the objects existing in it are described to be of the same nature as God. Since God, according to the followers of Pancharatra is constituted of six attributes such as knowledge, nitya vibhuti too should comprise all the six qualities. But such a view, they argue, does not sound good since that would amount to equating suddhasattva with a sentient being. Hence they contend that nitya vibhiiti is to be taken as jada.
Vedanta Desika does not agree with this explanation. The sacred texts declare that Ishwara is of the essence of jnana. The vigraha or the bodily form of such a Being cannot be made of anything other than pure sattvic substance. If it were made of material substance, it would be subject to change and decay. Therefore, it is appropriate to accept that suddhasattva is of the nature of knowledge implying that it is purely spiritual in character. The Pancharatra texts describe suddhasattva not only of the nature of knowledge (jnanatmaka) but also as self-luminous.
It has been pointed out that the released souls which are omniscient in the state of moksha, can apprehend it even if it is not self-luminous. The embodied souls do not cognise it in anyway since it is transcendental. So then what is the purpose of this self luminousity? In reply to this Vedanta Desika explains that it is not necessary that what is self-luminous should necessarily be the object of cognition. Ishwara is self-luminous but He is not perceived by us as such. In the same way suddhasattva can remain self-luminous, whether or not it is the object of cognition.
The dharmabhuta jnana which is an essential attribute of the self (jivatman) does not manifest itself during the state of deep sleep because it does not then experience any object; nevertheless, it does not cease to be self-luminous. In the same way suddhasattva is not cognised by us during the state of bondage but it can still remain self-luminous by virtue of its intrinsic character.