It really is a crazy situation to be in, one where an investor can't win. If you want to get out, then you're missing out on what the Fed promises to be a free-for all buffet lunch for the market. The Fed clearly said today that economic activity is too low, businesses need to be kept alive, and Congress has to get more money out to consumers.
But if you stay invested, you know you are holding assets that are being propped up by issuing debt. The government may be able to issue a lot of debt for a long time, but what if they can't? It is common sense that EPS expansion can't go on forever - investors ultimately want to own companies that increase earnings over time. In the US, the earnings come from consumers (or exports) and that's all gone in an unprecedented way. No one has any idea what earnings will be or how long it will take for things to return to 'normal'. In the meantime, many businesses will simply be unable to make money, but still have to service debt, pay rents, pay employees...
So, do you hold your bets for a few more days/weeks/months, thinking there's probably another few trillion coming from the Fed and Congress or do you rationalize that you're already pretty lucky to be able to sell stuff at inflated prices and sit out the roller coaster ride?
If only bonds or real estate offered a viable alternative! I'm sure there will be lots of great opportunities to buy stuff at reasonable prices at some point, I just hope I'm patient enough not to blow myself up in the meantime. I really have no idea what a reasonable S&P500 level is until we get some idea of earnings, so if it falls, how do you know when it has hit the floor?