Value theory encompasses a range of approaches to understanding how, why, and to what degree persons value things; whether the object of valuing is a person, idea, object, or anything else. This investigation began in ancient philosophy, where it is called axiology or ethics. Early philosophical investigations sought to understand good and evil and the concept of "the good". Today, much of value theory aspires to the scientifically empirical, recording what people do value and attempting to understand why they value it in the context of psychology, sociology, and economics.