2. Sometimes called “ESP,” the psychic ability to perceive things invisible to most people, such as auras, various health indicators, spirits, as well as things at a distance in space or time. It includes skrying.
Both clairaudience and clairvoyance, and other psychic skills, have been induced through hypnosis and self-hypnosis showing them to be innate to the human psyche.
"As part of the unfoldment of the human intellect into omniscience, the development occurs at a certain stage of human evolution of fully-conscious, positive clairvoyance. This implies an extension, which can be hastened by means of self-training, of the normal range of visual response to include both physical rays beyond the violet and, beyond them again, the light of the superphysical worlds…It is important to differentiate between the passive psychism of the medium, and even the extrasensory perception (ESP of parapsychology), and the positive clairvoyance of the student of occultism. This later, completely under the control of the will and used in full waking consciousness, is the instrument of research…to enter and explore the Kingdom of the Gods."
Hodson, Geoffrey: The Kingdom of the Gods, 1953, Theosophical Pub. House, Madras, India. (Page 9)
Suggested Reading –
Katz: You Are Psychic, The Art of Clairvoyant Reading & Healing
Owens: Spiritualism & Clairvoyance for Beginners, Simple Techniques to Develop Your Psychic Abilities
Slate & Weschcke: Psychic Empowerment for Everyone