The Spooky Science Behind Ouija Boards

Since the 19th century, the Ouija board has been viewed as both a dangerous instrument of the occult and a kitschy game to break out at parties. To use it, a group of people must place their fingers on the pointer, or planchette, and watch as the “spirits” glide it over the letters and numbers on the board, effectively spelling out their message. Some attribute this phenomenon to supernatural forces, while others point to deceptive pranksters. The real answer, however, is as spooky as it is scientific.

Source: Mental Floss