(In addition to being a straw man — because no flat-earthers are actually arguing with Justin/Riley — he/“she” is also setting up a standard trick we can call the Progress Fallacy: “Here is this provably wrong idea that people held in the past, and therefore, all ideas from the past can be disregarded as invalid.” Except, of course, that the scientific method itself is based on very old ideas, dating to ancient Greece. Now, back to Justin/Riley and “modern discourse.”)

(Except, of course, that the actual argument is about anthropogenic global warming [AGW], and it has been shown that the proponents of this claim have falsified “evidence” and disregarded alternative explanations for the observable changes in global temperatures. AGW proponents have engaged in fear-mongering and enlisted government authority to gain funding for themselves and to deny funding for their scientific critics. But please, Justin/Riley, continue to educate us.)