With the bull market in its 75th month of existence, investors are growing wary. They're not sure of what exactly, other than the assumption that stock market rallies are just not supposed to last this long.
In the last 50 years, one bull did survive a decade without a 20 percent bear interruption: the dot-com-fueled boom from 1990 to 2000.
But bears will argue an Internet-like revolution is not happening now to warrant that kind of sustained gain.
Bank of America Merrill Lynch sought to assuage clients by giving them five reasons this bull market will fight on. Here they are with accompanying evidence from other notable market seers.