I wouldn't say 'most' people are prone to negativity. I think it's probably that most people allow negativity to color their thinking, depending on circumstances, but I also believe most people make the necessary efforts to return to positive thinking as quickly as possible.
Zig ZiglarBefore a person can achieve the kind of life he wants, he must think, act, walk, talk and conduct himself in all of his affairs as would the person he wishes to become.
Zig Ziglar