"In reality," says mathematician John Allen Paulos, "the most astonishingly incredible coincidence imaginable would be the complete absence of all coincidences.

"In reality," says mathematician John Allen Paulos, "the most astonishingly incredible coincidence imaginable would be the complete absence of all coincidences." For a job like president, the circumstances are almost always ongoing a crisis or political anomaly. I imagine re-elected incumbents also had to face exceptional political circumstances, just were able to navigate through them with luck and skill.