It can be said that in Arthur Miller's All My Sons, the one thing Chris Keller loves more than his family is moral integrity, especially in the form of honesty.
We particularly see Chris's value of honesty when it begins to look like his father Joe played an intentionally criminal role with respect to a shipment of damaged engine parts. Ann's father Steve is in prison for intentionally shipping defective engine parts to be used in military planes. When 21 pilots are killed due to the defect, Joe Keller, Steve's boss, pretends he knew nothing of the defective shipment and has Steve indicted. Chris Keller has always believed his father to be completely innocent of the crime; however, later Ann hints that Chris should reconsider his father's guilt. Chris's response is to say, "Do you think I could forgive him if he'd done that thing?," showing us just how much Chris values honesty and moral integrity; he values these things more than he values his family or forgiveness.