Psychologist Steven Pinker in a TED debate with philosopher Rebecca Newberger Goldstein who argues that reason is the key driver of human moral progress. This is a wonderful debate with brilliant animations but it ignores the single most important fact that evolution not philosophy is the primary driver of moral progress.
Morality and the family
The family, although primarily an evolutionary adaptation, is a principal provider of stability and continuity as three or four generations of consanguineous individuals typically coexist. This is reinforced with the addition of relatives by marriage, the extended family, the inheritance of hard-wired memories in the form of photographs and artefacts belonging to our ancestors and also by the use of the family name. The family group is the basic building block of all human societies, no matter where in the world you were born and whatever your economic circumstances. It provides the security and stability necessary for the next generation to flourish. We are programmed to love and care for our children (or they would not survive) and in return they love us. Many of the most significant components of human behaviour like empathy, altruism and tolerance, are acquired and then constantly reinforced within the family.
It is from within this family setting that we first develop a moral awareness and concepts like fairness and justice. We have developed institutions of government and civil society that recognise fairness as a necessary component and we have created laws that prohibit discrimination and guarantee rights. It is reason that enables us to understand the origin of morality, but it is not the cause.