How does Brave New World argue that man is innately good?

I thought about this question and it is problematic. The themes and intent of the novel are to display the vacuous and superficial aspects of the human condition. There is really very little redemption to be found in any of the characters. The "savage" shows some traits that people have long since lost but then he eventually kills himself. People are just too messed up for him to continue. Bernard does question things but in the end, he serves his own self interest. I'm sorry if this is not the answer that you wanted. I think the book is more a cautionary tale rather than a story with any redemptive qualities.