Everything can be negative. Everything can be positive. Everything can just be ok too.
Outlooks ride the roller coaster of life. Sometimes giving the finger is the exact release of tension you need. Smiling, even when faked, lightens the mood. Indifference can create a peaceful pause.
All emotions complement of each other. You just can't get stuck too deep in one or the other. Perhaps Marcus Aurelius said it best:
"The happiness of your life depends upon the quality of your thoughts."
Even if those thoughts are negative or neutral.