Stocks are a safe bet, but only if you stay invested long enough to ride out the . that squares with the facts, and with the historical record
Declines are temporary, gains are permanent.
Surprise is the mother of panic.
You have to pick what you're going to be worried about. Markets are volatile, but retirement is certain.
Investment performance doesn't determine real-life returns; investor behavior does.
Long-term investment success is almost totally a function of how one emotionally handles declines in the equity market, as opposed to how one's portfolio handles them.