How Do You Know When You're Feeling Sad?

This is not an exhaustive list surprisingly of emotions, that it's just a doorway. If you can't find exactly what you're looking for, a find something close or again, you know, just stick with the color. I'd be curious about two things, hynd, where in your body do you feel that emotion? What sensations go on with that? How do i know when i'm feeling sad? Are we rewarded for expressing certain emotions and punished for others?"