Monday on Fox News Channel’s Tucker Carlson Tonight, host Tucker Carlson took on Bill Nye “the Science Guy” on the issue of climate change.

Carlson’s primary question for Nye dealt with what amount human activity was contributing to actual climate change.

“The core question from what I can tell is why the change?” he asked. “Is it part of the endless cycle of climate change or is human activity causing it? That seems to be the debate to me, and it seems an open question, not a settled question to what degree human activity is causing that.”

“It’s not an open question,” Nye replied. “It’s a settled question. Human activity is causing climate change.”

The two went back and forth, with Nye arguing the acceleration of climate change being 100 percent the fault of human activity. But at one point, Carlson hit back at Nye, who had in an earlier appearance said so-called climate change deniers were suffering from “cognitive dissonance.”

“So much of this you don’t know,” Carlson said. “You pretend that you know, but you don’t know, and you bully people who ask questions.”

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