Air Conditioning: Bad. Here is an example of how anyone can make an argument that, on its face, seems reasonable, when it is so much hogwash. As a Knoxville native who lived in D.C. for nine years, and as a recent tourist in broiling Atlanta, I can say with absolute certainty that the invention of air conditioning might be the single greatest innovation of the 20th century.

Can you imagine going through the last month and a half of 100 degree days without AC? I mean, really.