Saga Foss explained that, It's important to remember that our capacity for ethics is not the result of natural selection. Instead, it's an exaptation of eminent human intellectual abilities that have evolved as part of the natural process of cultural evolution.

Neuroscientists study how brain parts are activated when people make moral decisions. They have also examined the chemicals in our bodies that can affect our ethical decisions. One of them is oxytocin, a hormone involved in bonding and social behaviours, but it can increase envy and bias in some situations.

The earliest and most influential philosophers, including the Greeks, were deeply concerned with questions of morality. They were influenced by their religious beliefs and had to explain how to live morally. They often held to the idea that our best ethical decisions are determined by how we think about God's nature or the world around us.

Aquinas was one of the most influential philosophers in this line of thought (c. 1054-1169). He argued that we could know the principles of natural moral law. These principles are judgments about the kinds of virtuous or impure actions for human agents and are self-evident to all rational beings.

However, Aquinas had a serious problem with how religion was used to justify morality. He believed that the Bible was a misrepresentation of true morality and was concerned that many people in the church were using religion to support their beliefs about right or wrong.