One enduring trait that people remember about President Jimmy Carter is his honesty and forthrightness — some would say to a fault. Perhaps the most famous example of that came in an interview with Playboy magazine in 1976 when, as a presidential candidate, he said, “I’ve committed adultery in my heart many times.” That trait was on full display Tuesday when Carter and his wife, Rosalynn Carter, spoke to a packed Hanner Fieldhouse as part of Georgia Southern University’s Leadership Lecture Series.