Moral foundations theory, first proposed in 2004 by Jonathan Haidt and Craig Joseph,[69] attempts to explain the origins of and variation in human moral reasoning on the basis of innate, modular foundations.[70] Notably, moral foundations theory has been used to describe the difference between the moral foundations of political liberals and political conservatives.[71][72] Haidt and Joseph expanded on previous research done by Shweder and his three ethics theory.[69] Shweder's theory consisted of three moral ethics: the ethics of community, autonomy, and divinity.[73] Haidt and Graham took this theory and extended it to discuss the five psychological systems that more specifically make up the three moral ethics theory. These Five Foundations of Morality and their importance vary throughout each culture and construct virtues based on their emphasized foundation. The five psychological foundations are:
Harm/care, which starts with the sensitivity to signs of suffering in offspring and develops into a general dislike of seeing suffering in others and the potential to feel compassion in response.
Fairness/reciprocity, which is developed when someone observes or engages in reciprocal interactions. This foundation is concerned with virtues related to fairness and justice.
Ingroup/loyalty, which constitutes recognizing, trusting, and cooperating with members of one's ingroup as well as being wary of members of other groups.
Authority/respect, which is how someone navigates in a hierarchal ingroups and communities.
Purity/sanctity, which stems from the emotion of disgust that guards the body by responding to elicitors that are biologically or culturally linked to disease transmission.
The five foundations theory are both a nativist and cultural-psychological theory. Modern moral psychology concedes that "morality is about protecting individuals" and focuses primarily on issues of justice (harm/care and fairness/reciprocity).[71]: 99 Their research found that "justice and related virtues...make up half of the moral world for liberals, while justice-related concerns make up only one fifth of the moral world for conservatives".[71]: 99 Liberals value harm/care and fairness/reciprocity significantly more than the other moralities, while conservatives value all five equally. Ownership has also been argued to be a strong candidate to be a moral foundation.