Deontology provides a basis for special duties and obligations to specific people, such as those within one's family. For example, an older brother may have an obligation to protect his little sister when they cross a busy road together. This theory also praises those deontologists who exceed their duties and obligations, which is called "supererogation" (1). For example, if a person hijacked a train full of students and stated that one person would have to die in order for the rest to live, the person who volunteers to die is exceeding his or her duty to the other students and performs an act of supererogation.