There was a time when the nation was gripped by an epidemic that leaders felt went to the moral core of the country: bad posture. In her new book, “Slouch,” University of Pennsylvania historian Beth Linker recounts how curved spines, rounded shoulders, and slumped backs were considered reflections of moral fitness, the ability to hold a job, and even intelligence. We’ll talk to Linker about this “posture panic” that contributes to the ableism we see today, and we’ll hear from you: How’s your posture?