Herd mentality!

 The feelings of the crowd rather than being sum total of their feelings, nobody would subscribe to individually – as a bull / bear market develops, a lot of people are active part of it. And their feelings – bullish & extra risk taking in a bull market ; vice versa in a bear market- are so because they are part of a crowd & if they were not part of this crowd, then it is possible that their feelings would have been completely different. It is the herd mentality that makes people in a crowd have feelings that they might not have if they are not part of the crowd. In 1990’s the idea of all changing impact of I.T. leading to the dot. Com bubble etc..