I'm replacing a light fixture which fell out of the wall. Unfortunately the wires were pulled out of the fixture so I couldn't see how it was wired. But I do know that all the available wires were attached into the back of the light fixture. The other (ceiling) light was part of the circuit and both lights were controlled independently by two switches at the wall. My query is how is it possible that the two lights were switched independently even though all the wires were connected together in the back of one light fixture?