A. Point out that the author has not provided citations for any of his claims.
Notice some of the broad, sweeping claims made without support from any cited references:
"I think its capital city had the largest population of any city in all world history." All of world history would include modern cities that have vastly more population than any city in ancient Greece.
"I bet its military conquered nearly all of Europe, Asia, and Africa." That didn't happen -- thus no authoritative sources to cite to prove it did.
"I've heard a report that said" ... What report? Where? Cite the source!