I was struck by David Scharfenberg’s article about posture and the way it has been used in stereotyping one group or another (“Upright citizens meet stand-up guys,’’ Ideas, May 6). The sociology was interesting. I’m sure, though, that there was a practical reason for my parents’ admonition to “sit up straight,’’ beyond the stalwart appearance. Had I listened better and not hunched over my patients as a dentist for all these years, I believe my sciatic pain, due to my L4-L5 spinal displacements, would be at least less problematic. My physical therapist did not disagree.

Marc J. Zauderer

Winchester