Philip Pettit offers a new insight into moral psychology. He shows that attachments such as love, and certain virtues such as honesty, require not only their characteristic positive behaviours in the actual world (i.e. as things are), but preservation of those characteristic behaviours across a range of counterfactual scenarios in which things are different from how they actually are. The counterfactual 'robustness', in this sense, of these behaviours...