Our physiology has EVOLVED to release hormones that promote feelings of happiness and well-being when we engage in positive social interactions, such as showing love, kindness, or empathy towards others. This suggests that morality may have an innate component, as demonstrated by a scientific study which highlights the biological basis of moral behaviour:

https://www.sciencedirect.com/science/article/pii/B9780124201903000454

Abstract

Is there an innate moral sense? Scientific evidence, from child development, linguistics, and behavioral economics to neuroscience, moral psychology, and primatology reveals universal drives that constitute a biologically prepared moral architecture within human nature. This innate moral sense is akin to the innate predisposition for smell or language and suggests human beings are born with the prototypes of a sense that fosters anxiety when they witness others in distress and, similarly, promotes positive feelings when that distress is alleviated. Incorporating the concept of an innate moral sense into our models of social and political life would improve ethical analysis.

Nobody needs to instruct a baby on how to love their mother; it comes naturally thanks to hormonal influences.

Skin-to-skin contact between a newborn and their mother shortly after delivery is crucial and emotionally charged for both parties. Your touch and voice provide comfort and security for your baby, and this interaction triggers the release of oxytocin in your body.

Notably, childbirth and breastfeeding lead to a significant increase in oxytocin levels in women, promoting maternal bonding and nurturing behaviors.

Oxytocin, often referred to as the "love hormone," plays a crucial role in fostering attachment between parents and their offspring. While it was initially believed that only mothers experienced a surge in oxytocin levels during childbirth and breastfeeding, research has shown that fathers also exhibit similar hormonal changes when they engage in activities that promote bonding with their children.

Studies have revealed that emotionally invested fathers display increased levels of prolactin, a hormone typically associated with breastfeeding and sexual satisfaction, and vasopressin, a hormone linked to bonding and stress response in mothers. These findings suggest that fathers who actively participate in parenting experiences can experience hormonal changes akin to those of mothers.

However, the extent to which these hormonal changes occur depends on the level of proximity and interaction between the father and child. For instance, when a child sleeps with their parents, the father's recognition and response to the baby's cries, and playful interactions between the two, all contribute to strengthening their bond. In contrast, when there is a lack of physical closeness, the fatherhood effect diminishes.

As individuals mature, their moral compass is no longer solely determined by innate factors. Empathy, enlightened self-interest, and societal pressures become increasingly influential in shaping an adult's moral values. While empathy remains a vital aspect of moral development throughout a person's life, its significance wanes somewhat as other factors come into play.

In contrast, infants rely heavily on instinctual behaviours such as empathy and trust in their caregivers, which significantly impact their early moral formation. As the child grows and interacts more with society, external influences progressively shape their moral code. Ultimately, the interplay between innate tendencies and environmental factors contributes to the complex and dynamic nature of human morality.

We request the readers to please also read our article: What is the Purpose of Life as an Atheist?