Stocks are driven both up and down by the direction of money flow. Recently mutual fund managers boosted their stock allocation by the most since the beginning of the year, and as a result the first two weeks in September were pretty strong.
There is competition for invested dollars between stocks and bonds and as long as bond yields are so very low around the world there will be a tendency by investors to prefer the stock market. This has been true since the onset of the modern age, and despite events like the Chinese trade war or terrorist attacks such as we had this week in Saudi Arabia, that competition will underlie investors sentiment.
Until something truly spooks the investor expect stocks to remain their preferred investment of choice over bonds.