生活是世界上最罕见的事情。大多数人只是存在，仅此而已。
"To live is the rarest thing in the world. Most people exist, that is all."
Economics is the study of how societies use scarce resources to produce valuable goods and services and distribute them among different individuals. If we think about the definitions, we find two key ideas that run through all of economics:
唯一的限制是你为自己设定的限制。
Quality is never an accident; it is always the result of intelligent effort.