It is not possible to talk about Vishishtadvaita or Sri Bhashya without discussing the divya prabandham of the azhwars. The divya prabandha, which brings out the truth of the upanishads clearly, was the lamp used by srI rAmAnuja in the forest of the vedA.

Although the divya prabandha is not used as pramAnA in debates for obvious reasons, the arguments of sri vaishnavas stem directly from them, with sanskrit shAstras used as proof. Just for an example, to show how the divya prabandha is used by sri vaishnavas, I will illustrate one such instance.

I explained that in Vishishtadvaita, all perception is of the real. Nothing unreal can ever be perceived. This doctrine is justified by the Upanishads, but srI rAmAnuja writes in the Sri Bhashyam, "This (khyAti vAdA) has always been the view of ancient vedAntins".

Here, it is abundantly clear that the 'ancient vedAntins' he is alluding to are the azhwars. For in the ThiruvAimOzhi, Nammazhwar says,

uLan enil uLan; avan uruvam iv vuruvukaL
uLan alan enil, avan aruvam iv varuvukaL
uLan ena ilan ena ivai kuNam udaimaiyin
uLan iru takaiyodu ozivu ilan parantE

Meaning: He exists (for theists); He does not exist also implies He exists; - He has got such attributes and nature which can be described as existent as well as non-existent; He takes the forms as well as NO Forms; With such sthoola sareeram and sookshuma sareeram, He exists and is spread everywhere.

Nammazhwar here has firmly established the reality of perceived objects. The brief explanation is this - If someone says Brahman exists, he does. If someone says, Brahman does not exist, then it does not mean Brahman is non-existent. Since the atheist has said 'THAT (Brahman) does not exist', obviously 'that' refers to some form of perception, ie, that conception of brahman cannot be seen here. So, the non-cognition of that perception is actually real and what the atheist is seeing is real.

So, what it means is that, if Brahman is said to not exist, then he does not exist in the way that the atheist thinks he does. However, he does exist in some other way. As an example, someone may say, 'Rama does not exist'. He may be thinking of Rama as the one with the bow, the son of dasaratha. But the reality is that Rama, in that particular form, indeed does not exist now, at the present time. So, the cognition of the atheist, 'I do not see Rama' is real. Now, Rama does exist as sarvAntaryAmin and existed in the past in that particular rUpam as imagined by the atheist.

This is similar to how we say, 'The objects in the dream do not exist'. Yes, this is true, but they did have a temporary existence in the dream. So, perception is not negated. The BrihadAranyaka claims that the objects in the dream are real, which this ground for sath khyAti vAdA.

Thus, all perception is of the real. The perception of the atheist is also correct in the immediate sense that 'that does not exist in that way'.

This logic is used by srI rAmAnuja to justify sath khyAti vAdA that whatever is seen, is real, even when it seems contrary. It must be explained properly.