The perennial human interest in keeping a check on the costs of doing what we do is hardly surprising. In fact, the significance of this as an organising principle extends well beyond our own species: it plays an important role in the processes of biological evolution, where the viability of any organism depends on maintaining a sufficient degree of what we might call “energetic leeway” to weather the range of environmental variation encountered. In the human realm, it manifests in a perhaps more mundane way in the disinclination that people tend to have for working harder than necessary to do what they want to do—if there’s an easier way of satisfying our needs and desires, we tend on the whole to be good at finding it. Continue reading →