Uniformly in all such events there is the thought that there is something new in the world.

A Short History of Financial Euphoria by John Kenneth Galbraith.  Page 18.

Uniformly in all such events there is the thought that there is something new in the world. It can, as we shall see, be one of the many things. In the 17th century it was the arrival of the tulips in Western Europe, as the next chapter will tell. Later it was the seeming wonders of the joint-stock company, now called the corporation. More recently, in the United States, prior to the great crash of 1987 (often referred to more benignly as a melt- down), it was the accommodation of the mar- kets to the confident, free-enterprise vision of Ronald Reagan with the companion release of the economy from the heavy hand of government and the associated taxes, antitrust enforcement, and regulation. Contributing was the rediscovery, as reliably before, of leverage, in this case the miracle of high-risk or junk bonds supporting the initiatives of the new generation of corporate raiders and leveraged- buyout specialists.

In all speculative episodes there is always "an element of pride in discovering what is seemingly new and greatly rewarding in the way of financial instrument or investment opportunity. The individual or institution that does so is thought to be wonderfully ahead of the mob. This insight is then confirmed as others rush to exploit their own, only slightly later vision. This perception of something new and exceptional rewards the ego of the participant, as it is expected also to reward his or her pocketbook. And for a while it does.