Boeing closed at 66, up 2, for a rise of 6.33 points in the Dow.
One study showed a rise of 16 points in I.Q. by the age of 3, she said.
Yesterday's rise of 7.60 points put the average at 1,121.77; the peak in 1987 was 1,101.16.
The index failed to reach 1,800, however, and finished the half-day trading session at 1,791.1, a rise of 19.7 points from the Dec. 23 close.
It closed at 2705.6, for a rise of 17.8 points.
Southwest Airlines reported a 4.8 percent jump in capacity, and a rise of 4.6 points in load factor, to 73.9 percent.
Monday's gain for the Nikkei was its fourth-highest on record in terms of percentage, an extraordinary rise of 1,471.24 points, or 7.84 percent, to 20,229.12.
A majority of those polled, 51 percent said they expected combat, a rise of 12 points in three months.
It closed down 3.22 points, to 680.04, compared with Wednesday's rise of 5.10 points.
The tiny drop in the Dow came despite a rise of 1.25 points in the broader Standard & Poor's 500-stock index, to 470.18.