As the marginal investing bot continues to invest his marginal leveraged dollar-on-the-sideline on an equity market that, as Janet Yellen has explained to the poor, will create a "wealth effect" to sustain everyone through rainy days and retirement, we thought some context worthwhile. On December 5th 1996, Alan Greenspan - upon the recognition that equity market capitalization has bubbled to over 100% of nominal GDP - opined that investors had succumbed to "irrational exuberance." Since then, that 'exuberance' has become increasingly rational as the Fed pulls all its monetary-base expanding, deficit-funding, asset-purchases to keep the American Dream alive for a select (and shrinking) few... Irational-er and Irrational-er... But adjusted for the reality of a fiat world, things look a little different since the dot-com collapse inspired The Fed... As is clear - since the financial crisis, stocks have become completely dependent upon The Fed As The Monetary stock and flow indicate... And relative to debt... stocks have gone nowherefor 90 years... Charts: The Chart Store * * * "Clearly, sustained low inflation implies less uncertainty about the future, and lower risk premiums imply higher prices of stocks and other earning assets. We can see that in the inverse relationship exhibited by price/earnings ratios and the rate of inflation in the past. But how do we know when irrational exuberance has unduly escalated asset values, which then become subject to unexpected and prolonged contractions as they have in Japan over the past decade..." "How" indeed, Alan, how indeed?