The reason is because there are two different approaches to deal with illness: one,the positive psychological approach is that the illness is the absence of health, as opposed to health is the absence of illness.

究其原因，是因为有两种不同的方法,对付疾病，一是积极心理学方法,它指的是，疾病相当于不健康，相对地，健康等于没疾病。

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