Marjorie Sandor writes for the Masters Review on the art of writing the uncanny. Sandor explores the 19th century origins of the word, whose use in literature seemed to address the blurring of boundaries in history, science, and the emerging field of psychology:
You might go to “a canny man” to have a spell cast on an enemy, or to have one reversed. So you might say that from early-on, “canny” secretly contained the seed of its own “un.” A shadow-word just waiting to emerge.