A character of all multicellular organisms in the biosphere is that their life progresses through a defined series of sequential stages that collectively define a life cycle. In the animal kingdom, the life cycle stages are: conception, development, maturation, decline, and death. Though death may be inevitable, the duration of an individual’s life span is an unknown variable.
As a linear time line, the whole life cycle represents a process of aging. The conventional usage of “aging,” however, is generally associated with the phase of the life cycle defined as decline. The period of decline is characterized by a loss of physical and mental function, decrepitude, and infirmity, all traits of “growing old.”
The human aging period is of variable duration. Some individuals experience a long, protracted period of decline, while others are fortunate enough to have a vibrantly healthy life and then pass peacefully in their sleep, essentially without experiencing any infirmity.
Must a period of degeneration, “aging,” precede death? Can we get old without aging?