How Facebook works: Taco edition

Post: “Where can I get the best taco in Mexico City?”   Comment 1: “I like the chalupa at Taco Bell.” Comment 2: “I’ve never been to Mexico City, but I heard it’s really awesome.” Comment 3: “The taco was actually invented in 1495 by a Korean.” Comment 4: “The best taco in Los Angeles is at that one truck.” Comment 5: “No. The best taco in L.A. is at the other truck.” Comment 6. “Everyone knows the best taco in L.A. is in the backroom of that taco speak-easy that I’ve never act...