The Damocles reference article from the English Wikipedia on 24-Jul-2004
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Damocles

Helping orphans the way you would do it
In Greek mythology, Damocles was a courtier in the court of Dionysius the Elder. He mentioned that, as a person of power and authority, Dionysius must be very content and happy. Dionysius invited Damocles to a banquet, where he enjoyed very much sitting at Dionysius' throne. Damocles looked up and saw a sword hanging by a single piece of horsehair directly above his head and he thereafter realized the precarious position rulers are in.

The Sword of Damocles is a frequently used symbolic allusion to this myth, referring to the insecurity felt by those with great power due to the possibility of that power being taken away suddenly.