> As a parent, because you're in charge you feel like "because I said so" is reason enough to give.
>
> As a child repeatedly hearing this reason, you would quickly realize that your parents are imposing arbitrary rules, and don't really have good reasons for any of them.

I have to disagree with you here, with the caveat that you're absolutely right if this is all the reason you *ever* give.

But the reality is that the parents *are* in charge (or should be), and if parents cannot figure out how to do their jobs without an advisory ratings system in place to help them, then something is wrong.

I would further argue that "Because it's rated R" is an even worse answer than "Because I said so." Neither answer is helpful in helping the child learn responsible decision-making by setting an example, but both teach the child that sometimes he must trust in a more experienced authority until he is old enough to understand how to make those decisions responsibly for himself. However, "Because it's rated R" illustrates that that trust should be placed in an anonymous institution, while "Because I said so" teaches that that trust is placed in a parent, which is an important distinction for two reasons: (1) the child will one day grow up to be an adult like the parent, the implication here being that one day he'll learn and become capable of making those responsible decisions instead of letting others think for himself his whole life; (2) a personal figure who loves and cares is by far a better entity to learn to trust in.

Trust is an important thing to learn. If you don't, it's a long, lonely road ahead. If you can't trust your parents, who can you trust?

"Because I said so" is not going to come off as an arbitrary rule if the parents establish themselves as being sensible, trustworthy thinkers in other areas. Like I said, if that's ALL you ever say to your children, I agree with you. You're not teaching your children how to think or reason. But it's unreasonable to expect children to obey you only when you explain why. Sometimes children cannot understand. Excessive exposure to violence and other harsh components of the human condition, especially as sensationalized in modern entertainment, can be extremely warping to the development of young minds, but are children even going to begin to understand that when it counts?

Sometimes you can't give a reason to your children. Hopefully you'll be able to do better than "Because I said so," sure, but sometimes the rules are just not going to be adequately understood. But if you teach what you can and only impose sensible rules, children will figure out (perhaps only subconsciously, once adolescence hits) that, hey, their parents are rational and impose rational rules, so if they're imposing a rule, it probably makes sense, or at least is not arbitrary and unnecessary.