With the technical life span of humans (TLSh) as a foundation, a taxonomy consonant with modern medical science is presented which redefines the chronology of the terms middle-aged, aging, elderly, and aged. This redefinition is one inducer of behavioral change preceding attitudinal change needed to reach the goal: rectangularity of the survival curve. The indivisible triad of nutrition, health, and aging is the principal target for behavioral change at which health professionals can aim their resources during all phases of the life cycle.