Kinship is a dominant organizing principle of Fore society. Although genealogies normally can only be recalled to the second ascending generation, all significant social groups are assumed to be based on shared kinship, with the predominant ideology stressing patrilineal connections. Fore kinship, however, is not a simple reflection of actual genetic relatedness of individuals. Previously unrelated newcomers are easily incorporated as kin through various mechanisms of adoption, affiliation, and mutual consent. By fulfilling the obligations of loyalty and cooperation expected of kin, people become "one blood."
Kin Groups and Descent. The Fore conceive of their kin groups as being hierarchically organized and based on recognized patrilineal descent. The smallest unit is called a lounei, or "line." Members of a given line usually reside together in a single hamlet and are an exogamous unit. Several lines together form the next group level, the subclan, members of which live in close proximity to each other and consider themselves closely related; they may or may not be exogamous. The largest kin-based group is the clan, composed of several subclans; the clan is not exogamous. Although members of a clan recognize a common territory, it is not uncommon for some members to reside outside these boundaries.
Kinship Terminology. Fore terminology distinguishes siblings according to sex and relative age and uses the Iroquois scheme for cousin terms. In the first ascending generation, bifurcate merging occurs.