Evolutionary Morality

I have been reading Samuel Clemens' novel "Huckleberry Finn" to my nine year old step-daughter. We just read the section where Huck is wrestling with whether or not he should turn in Jim, the runaway slave and Huck's companion on his trip down the Mississippi. This morning in the car on the way to school she asked me, "why doesn't Huck know that slavery is wrong? Why is he struggling with this decision?"

I thought about this and came up with an example to help her understand -- I said, sometimes when everyone around us is doing something, we think it is the right thing to do. In fact, we don't know any better. Huck is actually very brave and very thoughtful to be questioning slavery. After all, everyone around him assume that slavery is the normal course of events -- even Jim! (and here comes the example) Its like today where we all drive around in cars without worrying about whether it is right or wrong. Your children might say to you, your parents really drove around in gasoline burning private vehicles!? Didn't they know it was wrong? But what choice do we have? Look around you and everyone does it and thinks it is normal...

To which she replied, "well THAT I know is wrong. We should ride our bicycles to school..."