Aesthetic simplicity is captured in Japanese [wabi] -- a moral principle emphasizing the experience of beauty as simple and austere through a serene and transcendental frame of mind. It originates in a notion of poverty and loneliness as a liberation from material and emotional worries, turning the absence of apparent beauty into a new and higher form of beauty. Richness is experienced through poverty and beauty through simplicity. In art it is associated with the beautiful, distinctive, aesthetic flaw that distinguishes the spirit of the moment in which an object was created from all other moments in eternity. It is the inspired limitation that gives elegance to the whole. Learning to perceive wabi in the environment is a process of aesthetic development.
Simplicity is valued in many religions as a virtue, the cultivation of which is a part of the spiritual discipline. In spiritual terms, simplicity indicates unity of purpose and heart, and a purity of approach which rejects intentions which, however worthy, distract from the love of God. This unity of purpose opposes duality and thus duplicity, deceit and double dealing. As Kierkegaard put it, "Purity of Heart is to will One Thing; and that is the Good". So in Taoism, unpretentiousness (simplicity) is human nature in its raw, unconditioned state like that of the new-born child. It is the innocent condition sought by the follower of the [Tao] who, returning to the source, to the primordial state, acts totally spontaneously and free from desire.
Cultivating spiritual poverty, or engaging in self-simplification, is the specifically the intensification of interior discipline, such as fasting, promoting spiritual detachment and the external indication of commitment to a specific way. Such poverty encompasses affective poverty - indifference to money and what it can buy. Poverty of spirit as an aspect of self-denial is part of the Islamic faith, abstinence from material goods and sensual pleasures having developed from abstinence from sin. The Sufis consider poverty as one of the [six stations of spirituality], a means of achieving liberation from that which distracts one from God; poverty of spirit acknowledges need for God. To St John of the Cross, spiritual poverty provides the detachment for quiet and repose, with none of the fatigue inherent in covetousness.