How high is the price we would pay for justice?

A sense of justice and injustice is an evolved moral emotion to signal to others that if exchanges are not fair there will be a price to pay. In the Ultimatum Game, in which one person is given a sum of money to divide with another person — with the stipulation that if the offer is accepted both keep the money, but if the offer is rejected no one gets any money — offers less than 30 percent of the sum are typically rejected. That is, we are willing to pay 30 percent to punish an offender. This is called moralistic punishment.

Everyone needs a little cuddle with an animal once in a while. For some at San Francisco International Airport, that animal just happened to be a pig. LiLou, a small, spotted Juliana pig, is the first pig to be certified in the Animal Assisted Therapy Program of the San Francisco Society for the Prevention of Cruelty to Animals. She is now part of the Wag Brigade, a group of therapy dogs who comfort passengers at the airport.