Intuitionists

Intuitionists, as proponents of this theory are sometimes called, support their theory by pointing to several sources of evidence.

For example, moral reasoning often comes ‘after the fact’ in moral judgments.  In other words, we often come to moral judgments quickly, on the basis of a first impression or intuition, and provide reasons or a rationalization for our judgments only after the judgment has occurred.

Moreover, it seems that there are cases in which people – psychopaths, for instance, who show a deficit in affective emotions like shame, grief, and sympathy – show no signs of deficiency in intellectual or rational capacities, yet seem to lack the ability to make (correct) moral judgments.  This seems to support the claim that emotions are necessary to morality.

The intuitionist position is classically referred to as a theory of moral sentiment.  Proponents of this theory point to the human tendency to sometimes favor, or privilege, family and friends in moral decisions to substantiate their claim.  Of the moral sentiment theorists, David Hume is perhaps the best-known.