Figure 3

Conceptual scheme of ageing as the accumulation of component causes throughout life Ageing starts with the accumulation of component causes A–E. The presence of these five component causes completes sufficient cause I, resulting in effect I, e.g. unsteadiness. In the following period, the addition of component causes F–H completes sufficient cause II, resulting in effect II, e.g. a gait disorder. The further accumulation of component causes I and J completes sufficient cause III, resulting in effect III, e.g. death (see also the description of the example).