conflicting moral judgments; that there is no method for resolving these conflicts that all would
find persuasive; and that these conflicts reflect conflicting obligations. Only the third claim is
wholly normative, the other two being open to empirical scrutiny. Let us consider pluralism and
absolutism more closely to see how cognitive science can be relevant in judging them.
Defining Moral Diversity and Pluralism
In defining pluralism, it is useful to note that some moral principles are more basic for an
agent than others. One may hold to the principle that it is wrong to gossip maliciously, but this
would not be a basic moral principle for a typical person. For most agents, the prohibition
against malicious gossip probably flows from some more general principle, (say) that suffering
should be minimized, in conjunction with some descriptive claim, (say) that malicious gossip
runs a great risk of increasing suffering. A moral principle is basic for an agent if the agent
would not try to justify it by appeal to any other moral principle (whether in conjunction with a
descriptive claim or not) (Brandt, 1984).
According to strong moral pluralism, for any humanly possible basic moral principle, it is
humanly possible that there is some other basic moral principle which conflicts with it such that
there would be no unanimous consent for resolving the dispute no matter how much information,
time, and leisure were available. The expression “humanly possible” is used to show that mature,
biologically normal humans are at issue. “Unanimous consent” refers to the community of all
humans and obviously indicates an ideal, since a conference of our whole species is infeasible.
The second occurrence of the phrase “it is humanly possible” is italicized to stress that this strong
pluralism can be true even if there is some basic moral principle which everyone happens to
accept. It is the mere possibility of irresolvable conflict which pluralism requires. Furthermore,
the word “any” is italicized to stress that there is no humanly possible basic principle immune to