The very first thing out of the lunatic's mouth, as justification for believing that "Planet X" was about to visit the inner Solar System, was: "the weather is crazy and there are more earthquakes lately." and "The on-line-real time seismology reporting system has been taken offline: why else would they do that?"
THe astronomer, when asked to justify why he didn't believe Planet X was about to arrive, said: "There is no evidence of the approach of a large unknown mass in the solar system; no orbital pertabations have been detected, nor anything else to suggest the presence of such an object."
At that point I fell asleep, knowing that the "debate" was for all practical purposes, over.