“There is always a disposition in people’s minds to think the existing conditions will be permanent,” Dow wrote, and went on to say: “When the market is down and dull, it is hard to make people believe that this is the prelude to a period of activity and advance. When the prices are up and the country is prosperous, it is always said that while preceding booms have not lasted, there are circumstances connected with this one, which make it unlike its predecessors and give assurance of permanency. The fact pertaining to all conditions is that they will change.” – Charles Dow, 1900
Source: Lo, Andrew W.; Hasanhodzic, Jasmina (2010-08-26). The Evolution of Technical Analysis: Financial Prediction from Babylonian Tablets to Bloomberg Terminals (Kindle Locations 1419-1423). Wiley. Kindle Edition.
You can probably see from Dow’s quote how trends do tend to continue, just because enough people think they will. However, price trends can continue into an extreme or a “bubble” just because people think they will continue forever. I like to ride a trend to the end when it bends and then be prepared to exit when it does finally reverse, or maybe reduce or hedge off some risk when the probability seems high of a change.
Image source: Wikipedia
Charles Henry Dow; November 6, 1851 – December 4, 1902) was an American journalist who co-founded Dow Jones & Company. Dow also founded The Wall Street Journal, which has become one of the most respected financial publications in the world. He also invented the Dow Jones Industrial Average as part of his research into market movements. He developed a series of principles for understanding and analyzing market behavior which later became known as Dow theory, the groundwork for technical analysis.