I highly recommend this discussion between Paul Bloom & Robert Wright. The topic under consideration is the psychology of pleasure, as reviewed in Bloom’s new book How Pleasure Works: The New Science of Why We Like What We Like. You can also find out about Bloom’s ideas in this exchange in Slate. The essentialism examined in Descarte’s Baby is being taken for another spin, though with a more precise focus. The bottom line is that pleasure is often contingent on more than proximate empirical sensory input; it depends on what you perceive to be the essence of the object of pleasure, even its history (or more crassly, its price). This truth may make the calculation project of the utilitarian heirs of Gottfried Leibniz pragmatically impossible.