joy and depression

Joy is the opposite of depression. Depression is a pain or sadness that persists unreasonably. Everyone experiences pain or sadness at times but hopefully you feel better after a while as you change and grow. Emotions are cyclical. Sometimes we're happy and feel good and other times it's the opposite, usually because of something that happens either way. But depression is when nothing helps and you're stuck in a hole through everything, good and bad. 

Joy is the opposite of that - a sense of well-being that persists beyond all reason, through good and bad.