Originating in Samkhya philosophy, sattwa or satva is one of the three gunas of Hinduism. It is a common means, along with the other two states, tamas and rajas, of categorizing behavior and natural phenomena in Hindu philosophy. In traditional Ayurvedic medicine, sattwa has been translated to mean "purity" and refers to one of three possible qualities (ie, gunas) or mental states of a person's mind. This typically implies that a person with this quality has a positive or even orderly state of mind. Such a persion is psychologically kind, calm, alert and thoughtful.