This email is about something that keeps popping up in controversial science issues: Carl Sagan's famous dictum, "Extraordinary claims require extraordinary evidence." Just this evening, I heard a psychologist on the Discovery Channel use this phrase regarding the question of whether or not "Bigfoot" exists. (Hardcore skeptics of the "paranormal" love to atack those who maintain that the creature might actually be real. It's really not a paranormal question at all, by the way-- only a crypto-zoological one.)
But back to Sagan. His comment about "extraordinary claims" sounds reasonable. It seems to be saying that we must have very high standards in scientific inquiry.
And indeed we should have high standards. But not a double standard. There is really no way to objectively and quantitatively determine the "extraordinariness" of a scientific claim. Therefore, there is no way to objectively say how "extraordinary" the evidence must be before we accept the claim. "Extraordinariness" is essentially an emotional consideration, not a scientific one. If you've done good, careful, science, your results should be taken seriously. If those results overturn previously held beliefs, that's just fine. Indeed, that's how science is supposed to work. Thomas Kuhn's book, "The Structure of Scientific Revolutions" is an excellent discussion of how science advances in fits and starts, as new data and viewpoints are ignored, resisted, and ultimately embraced.
"Extraordinary claims require extraordinary evidence." Another way to put this might be:
"Adjust your scientific standards to fit you emotional needs."
--Doesn't sound so reasonable now, does it?
Thursday, February 8, 2007
Gordon Kaswell on Skepticism
It's skepti synchronicity! About a week ago I received the following email from Oregon UFO researcher Gordon Kaswell. With his permission, I've posted his thoughts on skepticism below: