Or maybe a treatment will have "a placebo effect, " meaning it will make you feel better just because you have confidence it will make you feel better.

CNN: Is your doctor prescribing a placebo?

But, admonishes Mr. Keller, you can't overlook the leverage that such a fund adds to your portfolio just because owning it makes you feel special.

WSJ: The Intelligent Investor: Borrowing Against Yourself

Is it because you just feel the way the community's rallied around these women?

NPR: 17 min 50 sec

"It just takes a toll on you mentally, because you want to feel 100 percent healthy in everything you do, " Gay said.

WSJ: US sprinter Tyson Gay pulling back to push forward