One of the differences that jumps out at me about Lithuania and Greece is climate. I first learned about the importance of daylight for preventing depression (a

One of the differences that jumps out at me about Lithuania and Greece is climate. I first learned about the importance of daylight for preventing depression (and thus suicide) from an Internet comment about twenty years ago when I wondered why Canada's rate of completed suicide is as high as it is, even though I would have guessed that its access to guns for young people might be a little less than in the United States. The answer, given to me by a Canadian scientist, is that Canada is nearer to the North Pole and farther from the Equator, and so it has a long winter season with little daylight. In the old days, before United Nations statistics were on the World Wide Web, I actually went to a university library and looked up thick physical volumes of World Health Organisation statistics. The general relationship between polar latitude and high suicide rate, and equatorial latitude and lower suicide rate, holds up worldwide, with some exceptional-looking cases mostly explained by cloudiness. Low exposure to outdoor light is a suicide risk, and high exposure to cheery sunshine is a protective factor against suicide (but can lead to mania, known as "running amok" in some equatorial places). The author of the poem "Home on the Range" knew this: a place "Where seldom is heard a discouraging word / And the sky is not cloudy all day" like the Great Plains is protective against depression and suicide.