Alfie Kohn, writing for the New York Times:
A commitment to conditionality lives at the intersection of economics and theology. It’s where lectures about the law of the marketplace meet sermons about what we must do to earn our way into heaven. Here, almost every human interaction, even among family members, is regarded as a kind of transaction.
Interestingly, no research that I know of has ever shown that unconditionality is harmful in terms of future achievement, psychological health or anything else. In fact, studies generally show exactly the opposite. One of the most destructive ways to raise a child is with “conditional regard.”
Over the last decade or so, two Israeli researchers, Avi Assor and Guy Roth, and their colleagues in the United States and Belgium, have conducted a series of experiments whose consistent finding is that when children feel their parents’ affection varies depending on the extent to which they are well behaved, self-controlled or impressive at school or sports, this promotes “the development of a fragile, contingent and unstable sense of self.”
Bingo.