Tyche (Luck) was

The presiding tutelary deity who governed the fortune and prosperity of a city, its destiny. In Classical Greek mythology, she is the daughter of Aphrodite and Zeus or Hermes, and at this time served to bring positive messages to people, relating to external events outside their control. During the Hellenistic period, with dramatic socio-political changes starting with Alexander the Great, Tyche increasingly embodied the whims of fate (both negative and positive), eclipsing the role of the Olympic gods. The Greek historian Polybius believed that when no cause can be discovered to events such as floods, droughts, frosts, or even in politics, then the cause of these events may be fairly attributed to Tyche.

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