This document provides an introduction to the concept of happiness. It begins with an anecdote about a man who was surprised to see his wealthy friend unhappy despite his luxuries. This led to a discussion that true happiness comes from within and is not dependent on external factors like wealth or possessions.
It then discusses how people can react differently to the same situations, with some feeling unhappy and others maintaining stability and tolerance. An example is given of Immanuel Kant, who initially felt annoyed by a crowing cock but later realized his annoyance came from within rather than the external source.
The introduction emphasizes that what we allow into our hearts determines our happiness, not external discomforts. It compares how two people may experience the