Dr.Narayan Lal Kachhara Summary Development of Quantum Mechanics in Physics introduced an interesting phase in scientific history as it made some scientists to invoke application of consciousness to explain certain phenomena at micro level. Since the inception of this idea in 1950s many studies have been made to support or oppose the proposal. Part I of this paper reviews the quantum theories of consciousness, which essentially mean that consciousness is a material phenomenon, and presents arguments forwarded for and against this proposition. The Part II of the paper first presents the concept of soul and consciousness in Jainism and then briefly reviews the views of different religions and philosophies on this subject. Next the relation between soul and mind is discussed. Lastly the cognition phenomena are studied in the light of Jaina principles and the role of brain in this process is discussed.