Littlewood's law states that a person can expect to experience events with odds of one in a million (defined by the law as a "miracle") at the rate of about one per month.
Littlewood defines a miracle as an exceptional event of special significance occurring at a frequency of one in a million. He assumes that during the hours in which a human is awake and alert, a human will see or hear one "event" per second, which may be either exceptional or unexceptional. Additionally, Littlewood supposes that a human is alert for about eight hours per day.
As a result, a human will in 35 days have experienced under these suppositions about one million events. Accepting this definition of a miracle, one can expect to observe one miraculous event for every 35 days' time, on average – and therefore, according to this reasoning, seemingly miraculous events are actually commonplace.
-as cut-and-pasted from our friends at Wikipedia