According to rationalism, agents may fail to be motivated 
by moral judgments because they are irrational or because 
they fail to reflect sufficiently upon such judgments.  
According to sentimentalism, agents may fail to be motivated 
by moral judgments because they lack the appropriate desire 
or disposition. I suggest, however, that the failure to be 
motivated by moral judgments, or moral indifference, may be 
explained through impaired social relations. Specifically, 
I draw upon the work of Jeanette Kennett and Victoria McGeer 
to show how a particular case of moral indifference may 
resemble the social impairment characteristic of autism. 
While Kennett and McGeer focus upon moral agency, however, I 
conclude that attention to cases of moral indifference may 
also support their position – namely, that the choice between 
accepting either a version of rationalism or a version of 
sentimentalism appears to represent a false dichotomy.