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."
