Belief/value systems overlap so much with these other components of cultural systems largely because beliefs and values play such a pervasive role in culture. In our baseline definition of culture we suggest that culture consists essentially of learned behaviors and the template-effect by which a growing, changing culture is passed on from generation to generation. Beliefs and values affect virtually every learned behavior; the metaphorical template consists to a significant degree of belief/value systems. Thus, these systems are a central component of the larger cultural systems in which they exist.
Belief systems involve stories, or myths, whose interpretation can give people insight into how they should feel, think, and/or behave. The elaborate polytheistic mythologies of the ancient Greek and Roman civilizations are a good example of how belief systems can affect the daily life of a society's members and the role they can play in giving significance to people's actions. The most prominent systems of beliefs tend to be those associated with formal religions; however, any system of belief in which the interpretation of stories affects people's behavior -- a system of supersitions, for example -- can be a living, contributing component of a given society's culture.
A value system differentiates right feelings, thoughts and behavior from wrong feelings, thoughts and behavior. Value systems can and very often do grow out of belief systems. For example, one could argue that the value system behind Good Samaritan Law (a law which protects off-duty medical personnel from being sued for malpractie when they assist someone in an emergency) is a direct descendant of the Christian belief system -- a belief system whose story of the good Samaritin gives the law its name. However, other value systems -- those governing incest, for example -- appear to exist independently of formal belief systems.