Comment by kibwen

I think it's important to clarify that the question of whether or not everything has a cause is itself outside of science. Science is about determining what a cause is likely to be, using the universe itself as a source of truth, and constrained by fundamental limits on our ability to observe and experiment. Which is to say, even if the philosophers conclude that everything must have a cause, there is still no law that says that we (as scientific agents of a universe that is attempting to understand itself) are capable of determining every possible cause.