Desert and merit

The ideas of desert and merit are fundamental to the way we normally think about our personal relationships and our social institutions. We believe that people who perform good deeds and display admirable qualities deserve praise, honours and rewards, whereas people whose behaviour is anti-social deserve blame and punishment. We also think that justice is in large part a matter of people receiving the treatment that they deserve. But many philosophers have found these ways of thinking hard to justify. Why should people’s past deeds determine how we should treat them in the future? Since we cannot see inside their heads, how can we ever know what people really deserve? How can we reconcile our belief that people must be responsible for their actions in order to deserve credit or blame with the determinist claim that all actions are in principle capable of being explained by causes over which we have no control?