In experimental parapsychology, an ESP-test procedure in which a person attempts to identify concealed symbols or cards; mainly historical. For more, see: Psi Encyclopedia: Experimental Parapsychology ยท SPR glossary.
In experimental parapsychology, an ESP-test procedure in which a person attempts to identify concealed symbols or cards; mainly historical. For more, see: Psi Encyclopedia: Experimental Parapsychology ยท SPR glossary.