Are Stocks Overbought, Overvalued, Over-Owned & Over Exuberant?

One of the arguments emanating from the bear camp is that the U.S. stock market is overbought, overvalued, over owned, and over exuberant. And as you might surmise, those seeing the glass as at least half empty contend that such a combination is both (a) rare and (b) fatal to bull