Robert T. Carroll

About the author: Robert T. Carroll, author of The Skeptic's Dictionary and Becoming a Critical Thinker, is a professor of philosophy at Sacramento City College in California.

The distance between the stars makes it highly improbable that extraterrestrial aliens, if they exist, are visiting Earth. The theory that such aliens are abducting and experimenting on humans is implausible and lacks credible supporting evidence. People who say they have been abducted are fantasy-prone in ways similar to religious mystics who claim to have seen visions. Others may suffer from psychiatric disorders or sleep disturbances.

There is a widespread, though erroneous, belief that alien beings have traveled to earth from some other planet and are doing reproductive experiments on a chosen few. Despite the incredible nature of this belief and a lack of...