View full lesson: http://ed.ted.com/lessons/why-do-some-people-go-bald-sarthak-sinha If you are a living, breathing human being, chances are you have felt sad at least a few times in your...
========== Sadness is part of the human experience, but for centuries there has
been vast disagreement over what exactly it is and what,
if anything, to do about it. In its simplest terms, sadness is often thought of as the natural reaction
to a difficult situation. You feel sad when a friend moves away
or when a pet dies. When a friend says, "I'm sad," you often respond by asking,
"What happened?" But your assumption that sadness
has an external cause outside the self is a relatively new idea. Ancient Greek doctors didn't
view sadness that way. They believed it was a dark fluid
inside the body. According to their humoral system, the human body and soul were controlled
by four fluids, known as humors, and their balance directly influen...