Investors are skittish, and that means the market's recent gains are set to continue, according to Oppenheimer technical analyst Ari Wald.
"We're not seeing the type of euphoria that you typically see at a major top in the market," Wald said Monday on CNBC's "Trading Nation."
He points to what happened to sentiment just at the beginning of the month, as the market slid.
The S&P 500 fell as much as 3.4 percent from its August peak, which is "a run-of-the-mill pullback, but as soon as you get that first whiff of downside volatility, you really see the bulls run for the exits."
To make his point, Wald furnishes the chart of bullish-to-bearish sentiment as measured by Investors Intelligence, a "contrarian indicator," so called because when it shows a higher degree of bearishness, stocks are seen as more likely to rise.