another important feature of upanishads is that they don't speak about any god or rituals or a religion. They are equally acceptable to hindus muslims and christians and other people and even those who don't believe in god. Everything that had been said in this is practical and can be proved

wel, v hinduz get our wisdom 4rm upanishadz.. like u muslimz get ur inspiration 4rm hadiths:sahih bukhari Vol4, Book 52, Num80: Narrated Abu Huraira: Allah's Apostle said, 'Allah welcomes two men with a smile;one of whom kills the disbeliever,One who fights in Allah's Cause and gets killed and both of them enter Paradise, Later on Allah forgives the killer.