Meditation, Channeling, Psychics, Telepathy, Extrasensory Phenomena, Near Death Experiences, Dreams, Reincarnation and other dimensions.
Metaphysical literally means beyond physical or supernatural.
What makes something metaphysical?
Our world, environment and existence is perceived through our 5 senses. When our world and enviroment reacts in an unusual manner it is perceived as abnormal. Until the science is understood it is considered supernatural. For example, sickness physical and mental, was considered posssession, witchcraft, curses and a sign of sinfullness. Advancement in science, over the last 150 years has explained the existence of microbiology and the recognition of mental illnesses; treatment of both have saved untold lives and false imprisonments.
There is so much we have yet to discover about our world, other dimensions/realities. Remaining open minded about the unknown, and the continuation with the gnostism to bring in the light of wisdom and expand our knowledge may yet bring peace and Oneness with humanity.
Eventually, metaphysical phenomenon will be made common knowledge and natural sciences.