Source?

I'm arguing the perception of inflicting harm has moral weight. I'm borrowing the term from Jonathan Haidt and others. If the arbitor of the morality of the action perceives the action as causing harm, then the action is more likely to judged as immoral relative to an action that does not.

Here's an example - which man has acted more morally?

Man A walks down the sidewalk to his home and steps over a sleeping dog in his path.

Man B walks down the sidewalk to his home and kicks a sleeping dog in his path.

Most will not consider the actions of man B to be morally equivalent to those of man A because most consider man B to have caused harm.

This pattern can also demonstrated in the animal kingdom, many social animals will go out of their way to perform actions that do not harm third parties, all other things being equal. For example, lever A delivers a treat while lever B delivers a treat and a painful electric shock to the animal in the next cage.

This does not mean the perception of harm cannot be subjective or absolute harm reduction is the ultimate goal.

Edited for spelling and clarity

I haven't heard of any of these folks! I'm looking into them right now, thank you for the recommendations!!

I think I generally agree. I would emphasize the genetic predisposition to morality likely predates homo sapiens as a species.

Behaviours like a preference for harm reduction, preference for fairness, preference for autonomy, preference for established hierarchies, and a preference for loyalty can be seen in the non human animal kingdom. Furthermore, every human culture I'm aware of assigns a moral weight to sacred objects or actions. I would argue this is largely genetic and forms a basis of an "intrinsic" morality. Humans are born "primed" to accept hierarchy and sacredness as concepts, but it's up to the society to define the specifics. These moral concepts are fairly universal, and it's easy to imagine why such traits would be selected for in a social species.

As we have become more sophisticated we can describe an "aspirational" morality somewhat more seperated from genetics and intrinsic human nature. Usually these place lesser emphasis on sacredness and hierarchy and more emphasis on fairness and harm reduction. Most secular humanist morality models such as Sam Harris' moral landscape fit this "aspirational" morality category, but the ideal person described by various religious teachers could be placed here as well.

Edit: spelling