Markets mixed amid both optimism and warnings

Markets were mixed on Thursday.

The S&P 500 fell 0.3 percent but the STOXX Europe 600 rose 0.2 percent.

Earlier in Asia, the Nikkei 225 rose 0.2 percent but the Shanghai Composite fell 0.2 percent.

“Valuations are getting a little stretched, and it seems like there is some complacency in the markets,” said Wade Balliet, chief investment strategist at Bank of the West.

Indeed, Jeremy Siegel sees more gains for stocks in the remaining days of the year.

“I would say corporate tax reform could add another 10 percent to the market even this year,” said Siegel.

In contrast, Robert Shiller is “warning against complacency” as he sees signs of a possible bear market.

“[T]he US stock market today looks a lot like it did at the peaks before most of the country's 13 previous bear markets,” he wrote.