Insight, Intuition, and Imagination are the three aspects of higher thinking, also known as the three super faculties. They are developed through meditation and the practice of Tantra. They are the building blocks of the occult world and the magick way of life.
Within the International Nath Order this is the triad of higher thinking, not the triad of magick power. Iccha, Jnana, and Kriya are Will, Knowledge, and Action. These three faculties are Insight, Intuition, and Imagination. Shri Gurudev Mahendranath wrote that they let a person think freely, see error at speed, make their own texts, mantras, and rites, and wake the mind toward union with the Cosmic Spirit. THINK is the first key. The faculties are how that key is used. The invocation written for them is The Puja of the Three Super Faculties.