Join Date: Mar 2010
Location: Lovettsville, VA and Portland, OR
There's a logical fallacy called "post hoc, ergo propter hoc" also known as "false cause," to describe a kind of thinking that goes, "This happened right after that. Therefore, this was caused by that." Obviously it's not always true, but it does fill the bill when the mind is trying to make sense of things. If someone stops eating meat and falls ill soon after, the first thing the doctor will ask is "What major changes have you made lately in your life?" If it comes out then that the patient has recently gone vegetarian, the doctor will sometimes just say "Then don't do that. Go back to the way you used to eat, and we'll see if this clears up on its own." Then if it does clear up, doctor and patient (and patient's family!) will be completely convinced that the dietary change had caused the original problem. And they may well go on believing it forever, all because of a coincidence of timing. And it's impossible to argue against in a way that convinces the person who'd gotten sick. They have that strong, clear memory of trauma to back up their opinion. They were there. Nothing you say is likely to convince them otherwise.