I disagree with this. I class myself as a negative person because I am cautious, will always look at the disadvantages of doing something before looking at advantages, and will always look long and hard for possible problems. I work best with a positive person so that there is a good balance between us. A positive person will often overlook possible problems and try and proceed having only considered the positive side of things.

Basically my interpretation of what a positive person is, and what a negative person is, differs from yours.