Oh sure, it was reductio ad absurdum, just pointing out that the possibility of appendicitis wasn't by itself an argument against its continued existence - I don't know anyone personally who has ever been diagnosed with it...

> just pointing out that the possibility of appendicitis wasn't by itself an argument against its continued existence

Except that yes it is an argument against it.

Your reduction breaks down because it conflates "a reason" with "all reasons".