Not everyone has an IRA or 401K invested in the stock market, for those who do, the red warning light is flashing red: markets have reached historic extremes on numerous fronts.

Just like in 2000, proponents claim "this time it's different." Back then, the claim was that since the Internet would be growing for decades, dot-com stocks could go to the moon and beyond.

The claim the the Internet would continue growing was sound, but the prediction that this growth would drive stock valuations into a never-ending bubble was unsound.

Once again we hear reasonable-sounding claims being used to support predictions of a never-ending rise in stock valuations.

What hasn't changed is humans are still running Wetware 1.0 which has default settings for extremes of emotion, particularly manic euphoria, running with the herd (a.k.a. FOMO, fear of missing out) and panic / fear.

Despite all the assurances to the contrary, all bubbles pop because they are based in human emotions. We attempt to rationalize them by invoking the real world, but the reality is speculative manias are manifestations of human emotions and the feedback of running in a herd of social animals.

Here's a chart of financial assets as a percentage of Gross Domestic Product (GDP). (below) Note that in the "Glorious Thirty" years of the postwar era of broad-based prosperity, financial assets were around 3 times GDP.