In fact, one of the, maybe the most, elementary of moral principles is that of universality, that is, If something's right for me, it's right for you; if it's wrong for you, it's wrong for me.
Sinnott-Armstrong, Walter ed. It must, first, be stated that moral codes, like any other cultural systems, cannot survive for long if they prevailingly run in outright conflict with our biology.
Pulling the trigger can be a moral action only if you have the option not to pull it. This view of morality as concerning that which is most important to a person or group allows matters related to religious practices and precepts, or matters related to customs and traditions, e.
There are newspapers that have regular features with questions and answers concerning these matters. Some have succeeded and spread widely throughout humankind, like the Ten Commandments, although other moral systems persist in different human societies.
Society contributes to making humans what they are. Hammonds eds.