In the 18th century philosopher John Locke proposed a model of the human mind in which ideas associate or resonate with one another in the mind. In the 19th century, Romantic poets such as Coleridge and Shelley believed that inspiration came to a poet because the poet was attuned to the (divine or mystical) "winds" and because the soul of the poet was able to receive such visions. In the early 20th century, psychoanalyst Sigmund Freud believed himself to have located inspiration in the inner psyche of the artist. Psychiatrist Carl Gustav Jung's theory of inspiration suggests that an artist is one who was attuned to racial memory, which encoded the archetypes of the human mind.