Clairvoyance is a French word meaning simply clear vision. However, over the years clairvoyance has taken on an aura of the supernatural which causes more than a few people to close their minds to their own clairvoyant tendencies. Not surprising really when history reveals that a majority of people barely use their basic senses to perceive their world (i.e., sight, touch, taste, smell, sound).
For many people who limit themselves to perceiving their reality through their basic animal senses, people who use their finer senses of perception (i.e., clairvoyance) frighten them the way an eagle frightens a mouse.
Edgar Cayce (1877-1945) was a clairvoyant known and respected by all worldwide. I have been studying the new work of Dr. Wayne Dyer and so what I'm about to tell you know is especially fascinating to me: Dr. Dyer purports the importance of sound vibrations (espcially Ahhhmmmmm)as a way to open our spirit. Edger Cayce, I discovered, had the same philosophy: Cayce used a chant of that sound to open himself up to divine influences.
Cayce believed that through prayer we speak to God. In meditation, God speaks to us. I have not heard that sensible of an explanation for the difference between prayer and mediation before or since.