This exhibits the borrowing GP mentions: your ‘should’ does not necessarily follow from the stated priors. Why is compassion morally mandated by the priors and not competition, for example?

It’s at least an option for consideration. I shouldn’t have spoken normatively.

Is your position that compassion is only possible via religion?

Agree an option for consideration.

I don’t think religion is the only path, but that it has functioned as a prosocial positive-sum cooperating/compassion technology/mechanism in many cultural contexts. Not without downsides, of course.

That many today relatively reflexively default to ~‘we can all be nice to each other; this is obviously the (only) moral approach’ without stated precepts/priors/fundaments upon which that morality is moored I think tends to implicitly borrow priors from Western Christian tradition, albeit incompletely and sometimes critically so. Sam Harris’ recent appearance on Ross Douthat’s ‘Interesting Times’ podcast was IMO an example of this.