The most common ego identifications have to do with possessions, the work you do, social status and recognition, knowledge and education, physical appearance, special abilities, relationships, personal and family history, belief systems, and often also political, nationalistic, racial, religious, and other collective identifications. None of these is you.
You have probably come across "mad" people in the street incessantly talking or muttering to themselves. Well, that's not much different from what you and all other "normal" people do, except that you don't do it out loud.
Despite the fundamental importance of Bachelier's process, which has come to be called "Brownian motion", it is now obvious that it does not account for the abundant data accumulated since 1900 by empirical economists. Simply stated, the empirical distributions of price changes are usually too "peaked" to be viewed as samples from Gaussian populations.
[içinde: The variation of certain speculative prices. The Journal of Business, 36, 1963, 757-758]