mAdhva-mata can be termed a counter counter-religion (shAnkara’s bauddha base being considered).
Text torture
Btw, mAdhva-s are reputed for torturing texts (which is fair); but shAnkara torture (also very apparent to anyone who knows basics of language and has common sense) is relatively unknown. The former seems to be a (bad) response to the latter -
“You think you can torture texts? Haha you know nothing - I will show you what real torture is”.
A superior response would have been to show how you can make sense of contradictory statements without torture (as done in the rAmAnuja school).
Interpolations
Both shAnkara-s and mAdhva-s are accused of interpolation. shAnkara misattribution of hundreds of texts to shankara is also well known. Some examples elsewhere.
Divinity of shankara
Perhaps in reaction to shAnkara deification of shankara as an avatAra of shiva, mAdhva-s make him an avatAra of the asura maNimAn(??). They also consider madhva to be vAyu.
Mistreatment
Nominal shAnkara-s visit and feast in mAdhva-maTha-s without problems, while mAdhva teachings prohibit them from accepting water and food from smArta-s.
Also to be noted - learned mAdhva-s don’t consider most smArta-s real shAnkara-s (despite nominal confusion) since they don’t even study and understand shankara correctly.
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