The Chicago Board Options Exchange Volatility Index (^VIX), commonly referred to as the VIX, is a predictive gauge for the expected market volatility for the next 30 days. It's also sometimes called the "investor fear gauge." And today, that "fear gauge" is at an all-time low after plunging in the wake of the fiscal-cliff deal, when a lot of alleged market "uncertainty" was alleviated. In this video, Motley Fool financial analysts Morgan Housel and Matt Koppenheffer scrutinize some of the common folk wisdom about the VIX, including the idea that extremely low levels of investor fear predicate a market pullback -- and whether the VIX is even a good gauge of investor fear at all.