Do ghosts exist? Do scientific laws exist? Is there no difference between ghosts and scientific laws? Of course there is, and most scientists believe in scientific laws but not in ghosts. Why? Because a scientific law is a description of a regularly repeating action that is open to rejection or confirmation. A scientific law described some action in nature that can be tested. The description is in the mind. The repeating action is in nature. The test confirms or rejects it as a law. The law of gravity, for example, describes the repeating action between objects, and it has been tested over and over against external reality, and thus it has been confirmed. Ghosts have never been successfully tested against external reality (I do not count blurry photographs with smudges on them that can be explained and replicated by lens distortions or light aberrations). The law of gravity can be considered factual, meaning that it has been confirmed to such an extent that it would be reasonable to offer temporary agreement. Ghosts can be considered nonfactual because they have never been confirmed to any extent. Finally, although the law of gravity did not exist before Newton, gravity did. Ghosts never exist apart from their description by believers. The difference between ghosts and scientific laws is significant and real. Pirsig’s Paradox is resolved: all description is in the mind, but scientific laws describe repeating natural phenomena while pseudoscientific claims are idiosyncratic.
Michael Shermer, Why People Believe Weird Things (33)