The Mandaeans group existence into two main categories: light and dark. They have a dualistic view of life, that encompasses both good and evil; all good is thought to have come from the World of Light (i.e. lightworld) and all evil from the World of Darkness. In relation to the body–mind dualism coined by Descartes, Mandaeans consider the body, and all material, worldly things, to have come from the Dark, while the soul (sometimes referred to as the mind) is a product of the lightworld. Mandaeans believe the World of Light is ruled by a heavenly being, known by many names, such as “Life,” “Lord of Greatness,” “Great Mind,” or “King of Light”. This being is so great, vast, and incomprehensible that no words can fully depict how awesome Life is. It is believed that an innumerable number of beings, manifested from the light, surround Life and perform cultic acts of worship to praise and honor this great being. They inhabit worlds separate from the lightworld and are commonly referred to as emanations from the First Life; their names include Second, Third, and Fourth Life (i.e. Yōšamin, Abathur, and Ptahil).