木村：アメリカの高校で日本語を教えている友人が、円形脱毛症になってしまって。
佐藤：病は気からというけれど、よほどストレスがあったのでしょうね。
Yamai wa ki kara
Kimura: Amerika no kookoo de nihongo wo oshiete iru yuujin ga, enkei-datsumoo-shoo ni natte shimatte.
Sato: Yamai wa ki kara to iu keredo, yohodo sutoresu ga atta no deshoo ne.
Kimura: A friend of mine who's teaching Japanese at an American high school has developed a small round bald patch on her head.
Sato: They say that physical illness is often the sign of a troubled mind. I supposes she was under an awful lot of stress.
Yamai wa ki kara expresses the idea that physical illnesses are often psychosomatic- they are caused by deeper psychological problems, or a troubled state of mind.
When you feel sad, you lose your appetite. When you get angry, your blood pressure rises. Your heartbeat accelerates when you are taken by surprise. The worjldngs of the mind and body are closely interrelated.
Six months ago a friend of mine got a job teaching Japanese at a high school in the suburbs of Los Angeles. She set off with a suitcase fully packed with Japanese language textbooks and lots of high hopes. Then only last night she phoned me sounding very distressed: "The students behave terribly in class.
They don't listen to a word I say.
I'm stuck out here in the sticks. ... I just want to return to Japan." Before she left Japan she had seemed like a person who would never say such a thing. I couldn't make out what on earth had gone wrong.
I told her: "Yamai wa ki kara to iu desho (They say you can worry yourself sick, you know). If you carry on thinking like that, you'll end up getting ill." Then she told me, sounding extremely forlorn. "Two, enkei-datsumoo-shoo ni natte iru keredo, kore wa ki kara okita yamai ne (I've recently developed a bald patch, and I'm sure ifs caused by all this worry)." Being a woman, she manages not to let it show so much, but she told me she's lost a 4 centimeter-wide patch of hair. I really feel for her.
It has been reported that some terminal cancer patients recovered somewhat after undergoing a therapy in which they have a laugh by listening to amusing stories. We could also say kenkoo mo ki kara (physical well-being comes from a healthy state of mind). Or you could say that the more optimistic a person is, the less prone to illness they are likely to be.