A sound mind in a sound body, is a short, but full description of a happy state in this World: he that has these two, has little more to wish for; and he that wants either of them, will be little the better for anything else. Men’s happiness or misery is most part of their own making. He, whose mind directs not wisely, will never take the right way; and he, whose body is crazy and feeble, will never be able to advance in it.
"The best way to avoid trouble is to stay out of it."
【释义】社会常把内向病理化，凯根用实验证明：内向气质是大脑独特的生物设定，藏着深度思考与独立创新的宝藏。