Hamilton vs. Kant: Pitting adaptations for altruism against adaptations for moral judgment by Ana Lira and Chi-Yun Lee

Abstract Summary Subjects reported greater willingness to kill a brother or friend than a stranger to save five others of the same type. Hamiltonian presents: people are more willing to kill (against moral) one brother to save five People should be more reluctant to kill when brothers or friends involved according to Kant. But the reverse was found There is more in Kantian than altruism theory

Introduction Prominent evolutionary theories of morality say that moral judgement and behavior function to deliver benefits to others and/or prevent harm. - Support Hamilton’s theory on maximizing inclusive fitness

Views on Moral Dilemmas Ex) Dilemma - kill one to save five people, or not William Hamilton favored kin selection: a form of natural selection in which individuals can increase their fitness by helping close relatives, even at a cost to them - the concept of killing one over five is seen as consequentialist, based exclusively on outcomes Immanuel Kant argued that to kill one person over five would be an inviolable moral rule - nonconsequentialist

Purpose This study aims to find if people are more likely to support the Hamiltonian (consequentialist) perspective that make moral judgements based exclusively on outcomes OR support the Kantian (non- consequentialist) perspective that focus on the means used to accomplish the outcome, rather than solely on the outcomes.

Hypothesis 1: An increase in participant’s altruistic dispositions toward individuals in a moral dilemma will make them more likely to make decisions based on the moral constraint “do not kill” rather than the consequences. Hypothesis 2: An increase in participant’s altruistic dispositions toward individuals in a moral dilemma will make them less likely to make decisions based on the moral constraint “do not kill” rather than the consequences.

Study 1 Methods ●Introduced Trolley problem (both footbridge and switch scenario) using three conditions: 1. kill one brother, save five brothers 2. kill one friend, save five friends 3. kill one stranger, save five strangers Asked three sets of questions in regards to the Trolley problem

Sets of Questions First set: Asked whether or not they would push person off bridge - asked follow-up questions Second set: ●how many people would have to be on the tracks to be morally permissible ●how few people would have to be on the tracks for not pushing to be be morally permissible Third set: Ending comparison, which of two is more morally wrong? - asked follow-up questions

Results (footbridge & switch) higher odds of pushing for brothers or friends than for strangers moral judgements of pushing did not show differences across conditions more want others to push in the case of brothers or friends than in the case of strangers view pushing and not pushing equally wrong in all conditions

Study 2 For the second study, same questions were used using three distinct scenarios. Scenario 1: Footbridge problem (using two people instead of five) Scenario 2: Counterweight dilemma Scenario 3: Windstorm dilemma

Results larger portion reported that they would push to save two in brother condition than in the stranger condition pushing was seen less wrong in brother than in stranger on the seven-point scale (footbridge) more want others to push in the brother or friend case than in the stranger case basically replicate the effect shown in the first study

Discussion Subjects are more consequentialist when friends and relatives are involved Altruism systems and moral systems have distinct functions. Neither of them is the subcategory of another The function of the moral systems that Kant proposed is to coordinate their condemnation decisions with others This is a new hypothesis they proposed, so further research will be needed to test it.