Excerpt below from Common Sense on Mutual Funds by John C. Bogle, updated 10th Anniversary Edition published 2009 by John Wiley & Sons, Inc.:
My adversaries had more votes at the company than I did, and it was they who fired me from what I had considered "my" company. The merger - perhaps my first exercise of an entrepreneurial spirit - was a failure. But my failure was not in getting fired, but in jumping on the speculative bandwagon of aggressive investing in the first place. In retrospect, this failing was little short of disgraceful, and I can only be embarrassed about the fact that my determination to move quickly, my naïveté, and my eagerness to ignore the clear lessons of history led me into such an error of judgment. Life was fair: I made a big error and I paid a high price.