Just keep saying stuff like:

"Yeah...I don’t understand what you’re saying."

"I’ve never heard of that."

"Are you making that up...cause I don’t think it’s going to get any traction?"

"Nope...I’m not sure what you’re talking about."

"That’s a really weird thing to say."

"Where are you reading this stuff?"

"Anyone can make up anything and put it on the internet."

"I’m just really not following you."

"This is the first I’ve heard of this."

"Sounds weird."

"Are you sure you heard that right?"

"It’s not adding up. Yeah...sounds pretty fringe."

"You can’t believe everything you read online."

"This sounds like a conspiracy theory."

"Listen, you seem like a nice person. But..I think you need to be really careful about what you read and who you hang out with."

"This is the first I’m hearing about this. Something doesn’t smell right. I’ve got to do a little reading on this."

And make them repeat themselves and let 'em go crazy.