Are there any events in reality, or is everything a continuous process? If events exist, do they have precise beginnings and ends? When a photon hits an electron, is that an event? Does that "event" have a beginning and an end? Could the big bang be considered the only event? Can there be any events in a process? Related to the above question is the question: Are there any causes in reality? When two billiard balls traveling towards each other collide and proceed to travel in their respective opposite directions, what was the cause of that event? To make it a bit more difficult, say two balls are traveling in line and in the same direction, ball A at 10mph and ball B at 20mph right behind ball A, then ball B collides with ball A; what was the cause of that event?