"The "common sense" justifications for these dramatic moves are now well documented. The Federal Reserve (Fed) model, which compares earnings yields on the S&P 500 Index (the inverse of price/earnings) with the Treasury yield, clearly signals to load up on stocks. Common sense also tells us that profit margins are at an all-time high, so clearly it's a good time to be buying stocks. Yellen's dovish background, common sense tells us, is yet further reason to expect continued loose monetary policy and accommodation. And, finally, common sense dictates that recent upward gross domestic product (GOP) revisions, lower unemployment numbers, and a successful holiday retail season, means that of course it's time to load up on stocks. Here's the problem: We don't buy the common sense. And so, like the philosopher boy above, we choose to ignore it. We suggest you do the same, but for good reason."