The principle of one person one vote seems to emanate from a definition of person deriving not from gender, ethnicity, race or religion – but rather from membership in the species of homo sapiens. Further, this definition is understood to imply consequent right to influence issues affecting that person. This right to influence seems positively related to both the relative influence that issue has over that person and to the expertise that person has regarding that issue. So children as theoretically non-experts do not vote and persons vote for representatives in their home districts. Further, a vote for a regional post carries more relative weight than the same vote for a state post. This principle also allows for each person to influence other persons and so to exercise even more influence in the process. This influence relies upon human cooperation and not compulsion, however. In the US, any person of or over the age of 18 has the right to vote in a public election.