This study doesn't offer much hope for reaching consensus between conservatives and liberals. Conservatives allocate more moral consideration to their immediate family and friends, and progressively less moving out from there. Liberals are exactly the opposite, to the point that they allocate more moral consideration to inert entities such as rocks than to their own immediate family and friends.

From the study:

" Procedure. All participants completed a moral allocation task, in which partici-

pants allocated 100 “moral units” among the following 16 categories, pictured as

increasingly large concentric circles (see full depiction of task in Supplementary

Note 4): all of your immediate family; all of your extended family; all of your closest

friends; all friends including more distant friends; all acquaintances; all people

you have ever met; all people in your country; all people on your continent;

all people on all continents; all mammals on all continents; all

amphibians, reptiles, mammals, fish, and birds; all animals on earth including

paramecia and amoebae; all animals in the universe, including alien lifeforms; all

living things in the universe including plants and trees; all natural things in the

universe including inert entities such as rocks; all things in existence. Participants

read the following instructions:

'In this section, we would like to think about your capacity to help, to give,

to be charitable, to show empathy, and to be generous—in other words,

your capacity to behave morally. We can think about people having

different amounts of moral units—like currency—that they can spend on

others and can allocate to different moral circles. Some people devote all of

their moral units to one circle whereas others try to divide up their moral

units amongst multiple circles. Again, by moral circle, we mean the circle of

people or other entities in which you are concerned about right and wrong

done toward them.'

We also explained to participants that these categories were non-overlapping

such that giving to one category (e.g., extended family) would not include an

inclusive category (e.g., immediate family). Participants completed two iterations of

this task (order randomized). In one, they were asked to allocate moral units how

one should ideally divide them. In the other, they were asked to divide them as they

personally do so in their daily lives. These allowed us to assess differences between

actual and ideal moral allocation, but no meaningful differences emerged. The

categories allowed us to create composite moral allocation scores for humans only

(average of units allocated to the first nine categories) and for nonhumans (average

of units allocated to the last seven categories). In addition, participants also

completed a more qualitative measure of the extent of their moral circle by clicking

on rungs extending outward and representing the same categories as in the moral

allocation task (see Supplementary Note 4). This measure allowed us to create

heatmaps to visualize the relative sizes of liberals’ and conservatives’ moral circles.

This task was also counterbalanced in presentation with the moral allocation task,

and no order effects emerged."