And never before as today have we been so aware of our lack of unawareness - of how, daily, we might be failing to grasp all the ways in which multiple invisible hands harvest strengths and vulnerabilities from our exchanges, executing identity sections of our preferences.
To try to reassure investors, Enron said late Thursday that EnronOnline, its Internet-based trading exchange, executed more than 8,400 trades that day, a higher-than-normal volume.
The exchange executed 4,969,800 trades last month, according to the World Federation of Exchanges; it executed a little more than 5 million trades in March.
Today, though, electronic trading has once again taken king of the hill status as in 2012, 60percentt of all futures volume on U.S. exchanges was executed by algorithms according to industry analyst firm The Tabb Group.
If a brokerage firm sent an order to an exchange that executed it at an absurd price, then that firm did not live up to its obligations.
According to Bloomberg News, the exchange erroneously executed a trade of 100 shares of Apple that drove the iPhone maker's shares down sharply, to $542.80, triggering the circuit breaker on the stock.
Those competitors are now aggressively urging the S.E.C. to amend what is known as the trade- through rule, which holds that orders for stocks listed on the New York exchange be executed at the best possible displayed price.
In the old world traders were required to send every order to a registered broker-dealer who passed it along to an exchange or executed it themselves.
Electronic trading firms now trade on several competing exchanges and execute orders immediately to capture the best price available and drive down commissions, they say.
During the first decade of this century, the S.E.C. issued a series of rules that allowed new exchanges to execute stock trades.
