``The soul, by its interior vision, may see not only what is passing at a great distance, but it may also know in advance what is to happen in the future. The future exists potentially, determined by causes which bring to pass successive events.
``POSITIVE OBSERVATION PROVES THE EXISTENCE OF A PSYCHIC WORLD, as real as the world known to our physical senses.
``And now, because the soul acts at a distance by some power that belongs to it, are we authorized to conclude that it exists as something real, and that it is not the result of functions of the brain?
``Does light really exist?
``Does heat exist?
``Does sound exist?
``No.
``They are only manifestations produced by movement.
``What we call light is a sensation produced upon our optic nerve by the vibrations of ether, comprising between 400 and 756 trillions per second, undulations that are themselves very obscure.
``What we call heat is a sensation produced by vibrations between 350 and and{sic} 600 trillions.