The Poison Is In the Dose

"Every time we turn on a light, we are inadvertently taking a drug that affects how we sleep." (p.304)
-Chronobiologist Charles A. Czeisler

(I forgot to note this, but I think it's written circa 1800?)

At Day's Close: Night in Times Past. A. Roger Ekirch. Norton, New York: 2005.

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