To waste less energy, robots need to do less of everything: move less, and think less, and sense less. They need to be “lazy” like humans.

In many parts of the world, on many days, a ceiling fan is all you’ll need. Leave the ACs to those who really need them.

Elephants have their own, ancient geographies. “They walk 20 or 25 kilometres a day — their bodies need it.” Increasingly, in southern India, that brings them into contact, and conflict, with human beings.