The four weapons which Lord Vishnu holds in his hands are - Shankha, Chakra, Gada and Padma. The Conch signifies knowledge and dispels darkness of ignorance. Chakra is the most Powerful weapon Vishnu holds. It symbolizes mind. The Padma or Lotus in Lord Vishnu's hand is a symbol of creation. The Gada or Mace– which represents knowledge – is held in the lower left hand, which denotes "individual existence". The Vishnu Purana calls the Gada the power of knowledge.