The mathematician Charles Lutwidge Dodgson posed a big question about mirrors in one of his best-known books: Through the Looking-Glass (yup, Dodgson's pen name was Lewis Carroll). Natasha Gostwick of Storynory reads an excerpt that gets at the heart of the trouble: is mirror milk any good to drink? Neil deGrasse Tyson explains why this is a serious question, and introduces us to chirality, or the handedness of molecules. In fact, as Neil and Marcelo Gleiser of Dartmouth point out, all living molecules are left-handed. Which brings us to Marcus du Sautoy, who tells us the story of thalidomide...a cautionary tale about right-handed mirror molecules.

Up next, we meet a man named John Walter who swapped places with his mirror self. Kind of. He explains how changing his hair part changed his life, and how the experience convinced him that mirrors (and the reversed images they reflect) lie to us. We run John's theory by Mike Nicholls of the University of Melbourne, who admits John might be on to something about the way we perceive faces.

Here's Abraham Lincoln true

And here's Abe Lincoln flipped