In this great katha of Swami Brahm Dev Udasi he mentions what school of thought is Gurmat. When hindus asked a Udasi Sadhu what school is Gurmat is it Advait,Dvait,Shuddadvaita. The Udasi Sadhu over 100 year ago proved it is 'Bhagti Gyan Samucha" School. Have a listen to the katha also Swami Ji mentions a Udasi Sadhu over a 100 years ago who wrote a granth showing the superiority of Gurmat against the six schoools of hinduism and showing that Guru Nanak Sahib's Gurmat is Superior to all sc