The world or cosmos is multidimensional, a spectrum of many worlds. In most shamanic tradition we have upper, middle and lower worlds. In some mythic-shamanic traditions we have five, seven, nine, or more worlds, often arrayed around a central tree or axis, the axis mundi. Other names for these nonordinary realms are "spirit world," "otherworld," "faery world," and "dreamtime." In esoteric and theosophical traditions we usually hear of seven levels of consciousness, such as the etheric, the astral, the mental, and so forth. In the Indian and Tibetan traditions as well there are many levels or realms of consciousness, sometimes arranged in a circle on a wheel. In the shamanic traditions, and in the experiences of contemporary neoshamanic practitioners, with or without mind-moving substances, experiences of visiting other worlds are quite common. Also, of course, they are accessible via dreams. Alternatively, the person may feel that the veils, barriers or screens between worlds can become transparent or porous, so one can see and be in both the ordinary and the spirit world at the same time (and in the same place).