The balance between an openness to new ideas and a healthy skepticism...

This is from the book Capital Account and was written in 2001 during the tech bust, but it is probably timely for many technology companies today as well:

The challenge for investors is to distinguish the genuine innovations which create sustainable competitive advantage for companies and value for shareholders from the MacGuffins of this world. This requires a balance between an openness to new ideas and a healthy scepticism. In the last few years, we have seen many new investment concepts turn out to be nothing more than flagrant promotions. Even in the more questioning times that lie ahead, an aptitude for spotting absurdities in the stock market -- the financial equivalent of devices for trapping lions in Scotland -- remains an invaluable component in the fund manager's tool-kit.