"Introduction to Economics" is the first course that introduces you to the fundamentals of economic reasoning. It involves rationality, mathematics and experience. Today, the notion no longer seems to be convincing. Generally, economics revolves around a central concept called homo economicus which refers to a prototype of a rational, economic human being. In other words, it describes an individual who acts independently and who tries to match limited resources to unlimited needs. Nonetheless, this rational being does not exist anymore. We are living in a world full of people who spend more than they earn, confuse needs with desires, "sacrifice their future happiness for familiar unhappiness". How did we become like this? When and why did the economics lose this rational human being? What ...