The 'Atmaarpana Stuthi' is a hymn in Sanskrit language composed by Appayya Dikshitar, one of the great saints and proponent of Advaita Philosophy after Adi Sankara. It is a hymn in praise of Lord Shiva and is also known as ‘Unmattha Panchaa Shath’. Once Dikshitar felt that he has to put himself to a test as to whether his devotion to Lord Shiva was indeed true. He thought, ‘Suppose I become insane, will my mouth utter the name of Lord Shiva. If that be so, then it must be real.’ So, he embarked on an experiment. He made a paste of Datura seeds. These seeds are poisonous and if taken in, will make a person insane. He also prepared an antidote to this poison. He called his disciples. He gave them the poisonous paste and the antidote. He told them to give him the first potion for a week and write down whatever he said in that state of mind. After recording this, they have to give after a week, the antidote that would bring him back to normalcy. Indeed it was a remarkable experiment to find out how serious he was about Shiva. The experiment started. The disciples recorded what he said during that time. It was this hymn on Lord Shiva consisting of fifty verses. ‘Panchaa Shath’ means 50 and ‘Unmattha’ means “one who has lost his mind”. So, it is 50 verses composed during the period when he lost his mind.