Do you consider all historically successful and traditional moral values to be morally sound based entirely on their historical success and ..."traditional-ness"?
No. I also reason through moral values as they are presented by various sources. My religious foundations are one. Philosophers outside my religion are others.
eta: I'm thinking of another historically successful and traditional moral value: slavery. Do you consider slavery a morally sound value?
No, I don't.
You consider slavery a historically successful moral value? How so?