Most people argue that free will exists, but the main reason it exists is because of some metaphysical criterion, namely a soul.  However, a new study recently came out that many people attribute free will not to the soul, but to one’s mental capacity.  Thus, many people believe that free will is not a metaphysical concept, but a psychological one.  How does one measure this?

In the first trial, 197 demographically diverse Amazon Mechanical Turk volunteers considered the rule-breaking actions of a randomly assigned character or “agent.” That cast included a normal human, an “akratic” human with an inability to use his thoughts to control his actions, a cyborg with a human brain in mechanical body, an artificial intelligence in a human body, and an advanced robot.

Participants read about the agent and seven transgressions of varying seriousness and then rated the blame the agent deserved for each. Then the volunteers answered questions about the agent’s capacities, such as their ability to choose and to form intentions, and whether they had a soul.

The results showed a clear difference between having a soul and having free will. Volunteers generally said each human agent (normal or akratic) had a soul, but only said the normal human had free will. Meanwhile they resoundingly said the cyborg with a human brain had free will but generally did not believe it to have a soul.

When it came to blame, people judged the normal human and the cyborg (the two with a mind that had the ability to make choices) most harshly. The akratic human (despite having a soul in the estimation of most), and the entirely artificial robot received the least blame.

Statistically, the capacities that most predicted whether volunteers said an agent had free will and should be blamed for wrong actions were the ability to make a choice with intentionality and being judged as free from control of others. Having a soul was a poor predictor of being seen as having free will or meriting blame.

The notion of the soul, at least applied to free will, isn’t used that much.  Moreover, people may attribute free will to non-humans, such as robots.