Are there any attempts to prove the eternal blissful etc. self?

The mahaparinirvana sutra seems to claim that there is an eternal blissful and pure self 'Self' appears in the positive very many times in that sutra, e.g. [here (Chapter 33)](http://www.chinabuddhismencyclopedia.com/en/index.php?title=Nirvana_Sutra:_Chapter_Thirty-Three:_On_Bodhisattva_Lion%27s_Roar_(A)) ,,, > Knowledge ["jnana"] sees the Void and the non-Void, the Eternal and > the non-Eternal, Suffering and Bliss, the Self and the > non-Self. The Void refers to all births and deaths. The Non-Void > refers to Great Nirvana. And the non-Self is nothing but birth and > death. The Self refers to Great Nirvana. or [here (Chapter 37)](http://www.chinabuddhismencyclopedia.com/en/index.php?title=Nirvana_Sutra:_Chapter_Thirty-Seven:_On_Bodhisattva_Lion%27s_Roar_(e)) ... > ""The Eternal of Great Nirvana is the Self. "The Self is the Pure. "The Pure is Bliss. "The Eternal, Bliss, the Self, and the Pure are the Tathagata. > "O good man! For example, space is not the east, > nor is it the south, nor the west, nor the north, nor the four directions, nor up or down. It is the same with the Tathagata etc. e.g. [here (Chapter 23)](http://www.chinabuddhismencyclopedia.com/en/index.php?title=Mahayana_Mahaparinirvana_Sutra:_Chapter_23:_On_Bodhisattva_Lion%27s_Roar) ... > The Three Jewels of the Buddha, Dharma and Sangha truly exist, and the > Tathagata always expounds the essentials of all laws [Dharma] Did any Buddhist philosophers try to prove that nirvana is a self, or that a self exists?