Above all be of single aim; have a legitimate and useful purpose, and devote yourself unreservedly to it.

Above all be of single aim; have a legitimate and useful purpose, and devote yourself unreservedly to it.

最重要的是要有一个目标;有一个合理而有用的目标，并毫无保留地投入其中。

-- James Allen 詹姆斯·艾伦