Taming my inner bear as S&P 500 hits 4,000

MY inner bear was roused from hibernation this past week as the S&P 500 index pushed beyond the 4,000 mark for the first time.

Have stocks run up too much? Will investors who remain invested end up being disappointed with their returns a year or two from now? Is a crash waiting around the corner?

There is nothing particularly significant about the S&P 500 breaching the 4,000 threshold - other than that it is a big round number. But 4,000 is a level that few market watchers thought would be breached this quickly.