Uncaused
Part of speech: adjective
Definition: That which happens spontaneously, unintended and uninitiated. Since all things must come from something that causes them the uncaused cause is that one thing that began the chain of existance, often identified as God.
Fortuitous
Part of speech: adjective
Definition: Happening by chance; coincidental or accidental.Happening by a lucky chance; lucky or fortunate.Happening independently of human will.
Example sentence: It's good to keep in mind that prominence is always a mix of hard work, eloquence in your practice, good timing and fortuitous social relations. Everything can't be personalized.