Nahi Ninda Nyaya

Paramacharya asks us to adopt Nani Ninda NyayaThe purpose of exalting a particular deity over the another is not to depreciate the latter. The underlying idea is that a person who worships his chosen god has unflinching faith in him and becomes totally devoted to him. Such exclusive devotion is called "ananyabhakti". The idea here, however, is not to regard other devatas as inferior to one's own chosen deity- an example of "nahi ninda nyaya".

Tarka Sastra (science of dialectics, logic and reasoning) proposes “nahi ninda nyay” to support one’s theory. Glorify your view, but that doesn’t mean that the other view is flawed. 

With this nyaya, almost all contradictions can be neutralized, even Ramanujas also at times adopt this nyaya

Some quotes from Ramanujas, though the person representing may not be authentic, it reflects the peace loving nature adn wish to neutralize contradictions and doubts.

Srimath Ramayanam is considered most authentic by our Poorvacharyas and only out of 'Nahi Ninda Nyaya' Srimath Ramayana was compared against Trivaimozhi in Acharya Hrudayam by Sri Azagiya Perumal Nayanar. Further, Sri Pillai Lokacharya consisred "Srimad Ramayana" and Mahabharatha" as more authentic than Puranas and between the 2, 

Srimad Ramayana was considered even more authentic. You mentioned about Simad Ramayana and Sri Ramanuja. In Ramanuja Noortrandhadi, It is mentioned that Sri Ramanuja took to his heart the inner meanings of Srimath Ramayana.(Padi konda keerthi, Ramayanam ennum...)

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another e.g.

Lokacharya Panchasat Shloka 33

tvayi vilasati ra~Nge sheShatalpena pumsA jagati guruvara shrIdR^iShTipUrAbhiShikte | kathamiva bhuvanArya tvAm vinAnyam bhajante sati dinakarabimbe ke pradIpam vahanti || 

Meaning: 

bhuvanArya guruvara - O Lokacharya who is best amongst acharyas. tvayi vilasati - When you are shining ra~Nge - in Srirangam, shrIdR^iShTipUra abhiShikte - washed by the merciful flood from the eyes sheShatalpena pumsA - of the Lord who rests on the bed of Adisesha, tvAm vinA - leaving you kathamiva (janA:) bhajante - how will (people) seek anyam - another? dinakarabimbe sati - When Sunlight is there ke pradIpam vahanti - will anyone carry a lamp? 

Vyakhyana Saram:

In this shloka, Desikan states that Pillai Lokacharyar is like a Sun compared to others. Again, this is not to put down other acharyas, but to praise Lokacharyar ("nahi nindA nyAya"). In our sampradhayam, our Azhvars and Acharyas have been called the Sun, because, just as the Sun removes the external darkness, they were born and removed the internal darkness. Azhvar is called "vakuLa bhUShaNa bhAskara"; Thirumangai Azhvar is called "loka divAkara"; Ramanuja is called "rAmAnuja divAkara:". Desikan says that with this Sun present, why seek anyone else? 

Vedanta Desikan Thiruvadigale Sharanam

Pillai Lokacharyar Thiruvadigale Sharanam

Azhvar Emberumanar Jeeyar Thiruvadigale Sharanam 

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Sri Parasara Bhatta used to say that if one must seek refuge of our Lord, among the dasavathara,Varaha is the most perfect choice. Based on the "nahi ninda nyaya" (not denigrating others) he is reported to have said: Matsya avathara is sea bound so it cant extricate us from the sea of samsara. Koorma is itself pushed down into the sea by a mountain. Nrisimha is different above and below the neck so not to be resorted to. Vamana took over the three worlds by stratagem of showing tiny feet and then growing to gigantic proportions. Parasurama was rage personified. Rama(Bhattar's favourite in fact!) lost His wife for ten months. Balarama was too fond of drinking. Krishna, His wife Andal says, was always lying. We haven't seen Kalki yet. So Varaha, who without any shame(manam illa panri) took on the form of a boar and jumped into the dirty sludge and brought out Bhuma devi, is the one to be resorted to. Similarly He will extricate us from the "bheemabhavaarnavodare" the belly of the deep and dangerous ocean of existence.

It must be remembered that it was Varaha Perumal who gave the first guarantee that He would safely steer the prapanna to safety. Varaha charma sloka 

Stiththe manasi suswasthe sharire sathiyo narah...

"Ye men if you realise and remember with all your humors in harmony, that I am the Cosmos and Unborn when you are "mens sana in corpore sana", then when death is iminent and you are like wood and stone, I will remember my bhakta, devotee, and take him to the highest abode, paramapada."

It was this very Varaha who taught the easiest way to attain Him to Bhudevi. She repeated it to us when She took birth as Periazhwar's daughter, "Thoozhomai vandhu toomalar thoovi thozhudu, vayinaal padi manthinaal chinthithu pozha piyaiyum pukuthurvan ninavaiyum thiyinil thoosaakum ". If we come sanctfied, offering pure flowers, pay obeisance, sing with our mouths and think in our minds, the past transgressions and those that still stand will disappear like cotton in a fire.

Sri Ambujavalli sametha Sri Bhoovarahaswamy Parabrahmane namo namah.

Dr.S.Sundar Rajan MS ortho

Trichy 22 Sep 2010.

source 1, source 2

Let us all live in peace and harmony adopting Nahi Ninda Nyaya

Hari OM