1. The Neuroscience of Moral Decisions Philosophical and Legal Implications
Joshua Greene, Harvard University
Dana Center, Washington D.C., June

2. “Don’t blame him. Blame his brain!”
The Liberal Says…
“Don’t blame him. Blame his brain!”
“Most of the developmental research… measures behaviors, self-perceptions, or attitudes, but mounting evidence suggests that at least some of the differences between adults and adolescents have neuropsychological and neurobiological underpinnings.”
--Laurence Steinberg and Elizabeth Scott (2003)
“Less Guilty by Reason of Adolescence”
Assumption: If your brain is responsible for your behavior, then you are not.

3. The Conservative Says…
“Don’t blame his brain. Blame him!”
“By locating addiction in the brain, not the person, the [National Institute of Drug Abuse] has generated an unwarranted level of enthusiasm about pharmacology for drug addiction.”
--Sally Satel and Frederick Goodwin (1998)
“Is Addiction a Brain Disease?”
Assumption: If you’re still a person, then you can’t blame it all on your brain.

4. The Law Says… If he’s rational, blame him.
If he’s not rational, blame his brain.
“Rationality is the touchstone of [legal] responsibility.”
--Stephen Morse (2004)
“New Neuroscience, Old Problems”
Assumption: Rationality is what really matters for responsibility.

5. The Neuroscientist Says…
“Blame him? Blame his brain? It’s all the same!”
“I am my brain.”
--Thomas Nagel (1986)
The View from Nowhere
Assumption: Whatever responsibility is, it’s NOT a matter of blaming you instead of your brain.

6. A Case Study: The Child Molester
Burns and Swerdlow, 2003
Why does brain damage excuse?
Moral intuition (liberal and conservative): “The cause is something external to him--his brain.”
The Law: “Damage compromised his rationality”

7. A Thought Experiment: Two Villains
Science Project:
lousy genes
lousy experience
criminal mind
criminal behavior
A “Normal” Villain:
Same genes
Same experience
Same brain/mind
Same behavior

8. What do we care about?
We want to know whether the bad behavior is caused by something external to the person, where the person is a mind or soul distinct from his brain.
Problem: Is there an immaterial mind/soul? How do we know what it does?

9. What Do Souls Do? ? Does the soul have a “core competence?” Yes:
Moral Judgment
“Is there a soul?” translates to…
“Is moral judgment a purely physical process?”

10. Moral Judgment as a Physical Brain Process

11. The Trolley Problem

12. The Footbridge Problem

13. Personal Moral Dilemmas
Personal vs. Impersonal Moral Judgment
Medial Frontal Cortex
Dorsolateral
Prefrontal Cortex (PFC)
Superior Temporal Sulcus
Posterior Cingulate/ Precuneus
Emotion/Social
Cognition Areas
“Cognitive” Areas
(Bilateral)
Inferior Parietal Lobe
(Bilateral; Not shown)
Emphasize ToM and “up close and personal”
Bilateral
% change MR signal
Brain Activity
Non-moral
Dilemmas
Greene et al., Science, 2001
Personal Moral Dilemmas
Impersonal Moral
Dilemmas
Greene et al., Science 2001

14. The Crying Baby Problem
Transition
P.J. Loughran

15. Difficult Personal Moral
Series of Comparisons
Moral Dilemmas
Personal Moral
Dilemmas
Impersonal
Moral Dilemmas
Easy Personal Moral
Dilemmas
Difficult Personal Moral
Dilemmas
vs.

16. Prediction 1: Cognitive Conflict
Greene et al., Neuron (2004)

17. Prediction 2: Cognitive Control
Greene et al., Neuron (2004)

18.   Series of Comparisons vs. Moral Dilemmas Personal Moral Dilemmas
Impersonal
Moral Dilemmas
Easy Personal Moral
Dilemmas
Difficult Personal
Moral Dilemmas  
Judgment = “inappropriate”
vs.
Judgment = “appropriate”

19. Prediction 3: Utilitarian Cognitive Control
Note:
a priori ROI
matched for RT
Same stimuli (dilemmas)
Greene et al., Neuron (2004)

20. Prediction 3: Utilitarian Cognitive Control
Response about here (adjusted for lag)
N = 39, p < .005, cluster ≥ 8  
Greene et al., Neuron (2004)

21. Keeping a Promise vs. The Greater Good

22. Keeping a Promise vs. The Greater Good 
N = 22, p < .02, cluster ≥ 10

23. So What?

24. ? ? ? ? ?   A “Dual Process” Model cognitive control
controlled, conscious “cognitive” response ? 
conflict monitor
judgment
stimulus 
unconscious appraisal
emotional response ? ?

25. If we do find the soul…
If we don’t find the soul… or

26. Punishment Without Soul?
Two rationales for punishment:
retribution
deterrence

27. Pure Deterrence Thinking
Instead of asking…
“Was it really him, or was it just his brain?”
“Was he really unable to control himself?”
“Did he really understand what he was doing?”
We ask…
“What are the costs/benefits of punishing people like him?”
e.g. “Will other mentally disabled people be deterred?”

28. Pure Deterrence Thinking
Cold and inhuman?
Or super humane?

29. To summarize…
We’re going to be arguing about this stuff for a long time.
Because the real issue is metaphysical: dualism.
The law avoids this issue by focusing on reason, which is not what people really care about.
If dualism is correct, then we have to find the magic line between brain and soul.
If dualism is incorrect, then almost everyone’s thinking has to change.

30. Jonathan Cohen
Leigh Nystrom
John Darley
Kelly Lowenberg
NIH
NSF