Is skeptical thinking negative?

While leading a discussion about alternative medical therapies, the Phactor observed something to the effect of "Having a skeptical perspective keeps you from making such errors in thinking." One of my students then commented, "I hate being so negative. I hate approaching everything by saying "prove it"." Interesting. Is being skeptical widely viewed as being negative? Hmmm. Well, do you view being gullible as positive? In the discussion that unfolded the conflict arises with respect to personal testimony. Your friend/lover/parent/sibling/ tells you they XYZed and it cured their MNOs. Most certainly you do not respond by saying, "Prove it." You just have to think it. As a hardcore skeptic, the Phactor never doubts the sincerity of such advice; they are trying to help, and the best you can say is, thanks, I'll look into it. Only a couple of weeks ago, the Phactor suggested to a person in the 3d tier of our social circles that she "may have benefited from a placebo effect" and it resulted in a frostiness that lasted the rest of the evening. Later her husband told me on the QT that he agreed. So no need to be unnecessarily confrontational, although in this particular instance, after relating her treatment and cure, she asked what others thought. The correct response is to ask for a bit more wine, s'il vous plait.