News Here's why Ash in Pokemon never gets old

[Nightrider]

Arbitrary age​

According to the arbitrary age theory, the label of age has a different significance in the Pokémon world than in the real world. In their culture, the numerical "age" of a person is not representative of the number of years which they have lived, but representative of the person's familial status. When a person comes of age and is ready to head out into the world of Pokémon, they are labeled "ten." When a person has children, they are labeled "twenty." When they have grandchildren, "fifty." Other ages may exist but there is not enough evidence to deduce these ages and milestones in one's life. The theory argues that these seemingly young ages for things like having (grand)children are similar to the surprisingly young age at which children come of age. Ash may well have been alive eighteen years, but hadn't earned the position of more than "ten." Brock's familial role is most accurately described with a half-age, "fifteen". He doesn't have children of his own but he takes care of his younger siblings in the absence of his parents.

History of the Pokémon world (anime) - Bulbapedia, the community-driven Pokémon encyclopedia

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