In Healing Back Pain, Sarno writes "...herniated disc material is rarely responsible for pain or any other neurological symptom"(p. 101) And: "My conclusion that most disc herniations are harmless is based on seventeen years of treating such patients with a high degree of success, leading to the impression that the extruded material is not hurting anything; it's just there (p. 101) He writes more about this in The Mindbody Prescription. Just check the book's index for relevant passages. Years later, these early finding are backed by other big names engaged in the science around TMS, Howard Schubiner, for example.