Pagan Celtic Spirituality understood that all of existence has a cyclic nature, and that there is a direct continuity between the material world and the otherworld. Druidic teachings, that have come down to us through Welsh tradition, recognized that there is an unseen world that interpenetrates and affects the visible world. Things are just not what they seem. Everything exists on several simultaneous levels. Human beings can understand things as having three levels: the physical, the spiritual, and the symbolic. Thus, Celtic culture was integrated with nature, and expressed itself through the multiple possibilities of life itself. Celtic religion taught the reincarnation of all individual souls, and the appearance of divine beings on Earth.