Stock market volatility brings on more volatility

Where it stands: Investors simply can't work out what stocks are worth in a world dominated by President Trump's trade war. A quick recap here:

• Thursday, April 3: Stocks reacted to the "Liberation Day" announcement by opening down 3.14%. At their lows for the day losses reached 4.9%, a big move, but understandable given the magnitude of the news.
• Friday, April 4: Stocks dropped another 6%, over and above their losses the previous day.
• Monday, April 7: Stocks continued to fall in early trade but then surged 8.5% on a curiously prescient yet apparently false headline about National Economic Council director Kevin Hassett. Then they fell back down.
• Tuesday, April 8: With nothing solid to anchor to, stocks dropped 6.8% from the intraday high to the intraday low.
• Wednesday, April 9: Stocks close up 9.5% in the wake of Trump pausing most reciprocal tariffs and narrowing his focus onto China.
• Thursday, April 10: Stocks fall as much as 6.3% from the previous close, for reasons of a market nature.

TLDR: The quietest day in the markets was the day immediately following the big Rose Garden announcement.

Between the lines: Most observers believe at least in some weak version of the efficient markets hypothesis, where stock prices represent the wisdom of the crowds in terms of how much companies are worth.

• As such, they assume that stock prices move in reaction to new news, and that a large movement in stocks means something important has changed in the world.
• In a world of radical uncertainty, however, stocks can move huge amounts for no particular reason at all. Especially in down markets, rallies are often "short, sharp, and ferocious," per Sosnick.

The bottom line: This market is heaven for volatility junkies.