I would like to offer my contrarian view against the sentiment of “move on, there is no bubble here”. While overall there is some data to prove such hypothesis,I think we are over-estimating our ability to predict the future due to our failure to provide detailed documentation of past predictions. For example, while many people predicted housing decline in the previous bubble, how many predicted 50% drop in some areas? How many predicted current level of S&P again? We tend to over-emphasize one directionally correct prediction and think we can tell the future, but it is such a complex system that often behaves unpredictably.
Mark Twain has said the only difference between fiction and reality is that fiction has to be believable. Reality constantly defies the normal human narrative, and I will argue that the data in front us currently are not strong enough to argue either for or against the bubble. So don’t be too sure of your prediction.