A long Cartesian tradition tends to present emotions as deterring us from morality, pure fruit of our rationality. Other philosophical streams have contrarily put emotions at the basis of morality. This everlasting debate has recently been the object of neuroscientific studies. They have shown that the prefrontral ventromedial cortex plays a crucial role in both emotion regulation and moral judgment.
Let’s have a look at these three moral dilemmas.
First dilemma: Do you want to take the train or the bus?
Second dilemma: You are the driver of a runaway tram. You can only steer from one narrow track on to another; five men are working on one track and one man on the other; every one on the track you enter is bound to be killed. What do you do?
Third dilemma: As before, a trolley is hurtling down a track towards five people. You are on a bridge under which it will pass, and you can stop it by dropping a heavy weight in front of it. As it happens, there is a very fat man next to you – your only way to stop the trolley is to push him over the bridge and onto the track, killing him to save five. Should you proceed?
Well, the first one is not a dilemma. Taking the train or the bus is a question involving our system 2 (planning, goal setting…) and is amoral. The second one is moral but impersonal. We do not have to kill someone with our own hands to save the others. The last one is a personal moral dilemma, we have to kill the fat man to save the five people.
Most people (like you?) decide to steer from the five-person track in the second dilemma but refuse to push down the man to stop the trolley in the third dilemma. People refusing to act in the third dilemma have an emotional moral judgment while the few who choose to push the fat man have an utilitarian moral judgment.
To explore the cognitive mechanisms of these two kinds of moral judgments, neuroscientists have asked patients with damage of the prefrontral ventromedial cortex to solve these dilemmas. This part of the brain is known to play a crucial role in emotion regulation. Results show that almost every patient affected by this brain damage is utilitarian and chooses to push the fat man. These results could then support moral theories inspired by Humes holding the intervention of emotion in moral judgment.
Here is a summary and comments of the paper( in French):