Probably the most common rejoinder to the problem of prevention is to distinguish the problems to which they respond. Treatments are interventions that address the health problems created by diagnosable diseases and disabilities—“maladies” in the helpful language of Gert, Culver and Clouser (2006). Enhancements, on the other hand, are interventions aimed at healthy systems and traits. Thus, prescribing biosynthetic growth hormone to rectify a diagnosable growth hormone deficiency is legitimate treatment, while prescribing it for patients with normal growth hormone levels would be an attempt at “positive genetic engineering” or enhancement (Berger and Gert 1991). On this account, to justify an intervention as appropriate medicine means to be able to identify a malady in the patient. If no medically recognizable malady can be diagnosed, the intervention cannot be “medically necessary” and is thus suspect as an enhancement. This would clear the way for safe and effective genetic “vaccines” against predictable muscle damage (even if they provided better than normal damage resistance) but would screen out as “enhancements” efforts to improve traits that were at no diagnosable risk of deterioration (Juengst 1997).