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The Clash of Logic and Emotion

aeraeber's picture

As much as can be established, based on analysis of the currently available data, human morality is based on the interaction of two very different systems. One system is responsible for the cold, calculating morality that causes people to say that it is morally permissible to flip a switch in order to kill one person instead of five. This kind of morality is based on numbers and logic without the influence of emotion. The other system, however; is very much based in emotion. The majority of people would not push a large man in front of a train in order to save five people. The numbers are the same, killing one to save five, but people are horrified by the thought of pushing another person in front of a train (Koenigs). Clearly, these two systems are in conflict with one another on a regular basis. At times people are even consciously aware of the conflict, making it difficult to make a decision in the face of a moral dilemma. Many of the most hotly debated modern politically issues, abortion and gay marriage to name a few, often display this conscious moral conflict. Someone may not choose to have an abortion themselves, but they may still believe that abortion should be legal (Saletan). This certainly raises several questions: Why do both systems still exist? Should we favor one over the other? Or even go so far as the completely ignore one of the systems?

Logical, utilitarian morality certainly has its advocates, people who believe that it is more reliable, that it can be defined more completely, perhaps even made universal. Some people see a movement towards utilitarian morality as a way to solve the ethical conflicts that exist between cultures because it inherently lacks a cultural bias (Saletan). This is sort of black and white, clear-cut morality may very well be where Western society is headed, but it is not necessarily any better than an empathic morality. Drawing a clear line between right and wrong, without a consideration of the circumstances may be easier than considering the emotional side, but it can also necessitate outcomes that can be shocking. Utilitarian morality focuses on the good of the many, so, from a utilitarian perspective, smothering a crying child to save the rest of the family hiding in closest from an armed robber is permissible. Emotions are a key part of who we are, of what makes us human , attempting to create a morality that is based solely on logic would destroy something our humanity. Of course, a purely emotional morality isn’t the answer either. It has no real lines at all and as such is too transient to be the basis of an ideological system. Cultural biases and stereotypes are also deeply intertwined with emotional morality, making it less reliable in many situations than a utilitarian morality.

If a morality based in both logic and emotion was not adaptive, it’s unlikely that it would still exist in the human brain. It is inherently a strange system, since it creates conflict rather than reducing it, so the fact that it evolved at all implies that it works very well just the way it is. One moral reasoning system isn’t stronger than the other in people with healthy brains. “Usually, the human brain is of two minds when it comes to morality -- selfish but self-sacrificing, survivalist yet altruistic, calculating but also compassionate” (Hotz). In some dilemmas only one is activated, but generally they are both involved. Emotional morality is ancient, present in other animals as well as humans. It is the basis of trade systems and random acts of kindness, as well as disgust at unhealthy behaviors and horror at behavior that harms others. Utilitarian morality is a much newer, likely purely human, invention that came with the advent of language. Clear cut rules and explanations for moral decisions become the basis of moral philosophy and religion, essential elements of larger societies, especially those that are not kin-based (Wade). In modern society, one system cannot exist without the other. People are not computers following Boolean logic. While we need guidelines, room needs to be left for interpretation and an understanding of the circumstances of the event in question. Certainly a person who causes the death of a friend by putting poison in his coffee, sincerely believing that it is sugar should not be executed for murder ("Study Narrows Gap Between Mind and Brain").

It comes as no surprise that the two moral systems are the result of separate neuronal networks in the brain. The emotional moral system is based at least partially in the ventromedial prefrontal cortex, and damage to this area causes people to make far more utilitarian moral decisions. They are much more likely to find it morally permissible to kill one person to save many (Koenigs). Another study found that portions of the brain associated with emotion, including the medial frontal gyrus and the bilateral angular gyrus were more active on an fMRI, when people made personal moral decisions. Personal decisions are those in which the participant is actively involved in the dilemma, like pushing one man in front of the train to save several others. Dilemmas that were considered impersonal, like flipping a switch that would save five people but kill one, involved increased activity in the same cognitive areas as other kinds of abstract reasoning (Greene). When we make moral decisions in which we are not highly involved, then, we think just as we would when solving a puzzle or critiquing a novel. But making us part of the situation, giving us an active role, changes things. Neuronal networks involved in emotion are activated and our two systems of moral reasoning clash.

Religion and philosophy claimed morality as their sole province for hundreds of years, but advances in imaging and computer technology have made it possible for morality to be considered from a biological point of view. People have always wondered how we decide what right and wrong are and why those concepts don’t have identical definitions in every person. The concept that morality is based in the neuronal networks in the brain, and two separate, and sometimes conflicting, neuronal networks exist to control moral reasoning goes a long way towards a useful, “less wrong” explanation of morality. Everyone’s brain is different, so if morality is brain based, it makes sense that people have different moral standards. A neurobiological explanation of morality doesn’t necessary throw religion out the window, but it does displace it as the sole basis of morality. For some people that is an uncomfortable concept, and it certainly raises new issues in ethics.


1)Dawkins, Richard. The God Delusion. “The Roots of Morality: Why Are We Good?” New York: Houghton Mifflin, 2006. 241-267. Print.
2)Greene , Joshua, R. Brian Sommerville, Leigh E. Nystrom, John M. Darley , and Johnathan D. Cohen . " An fMRI Investigation of Emotional Engagement in Moral Judgment." Science 293.5537       (2001):2105-2108. Web. 6 Apr 2010. <>.
3)Hotz , Robert Lee. "Scientists Draw Link Between Morality And Brain's Wiring ." Wall Street Journal 11 may 2007: n. pag. Web. 16 Mar 2010. <>.
4)Koenigs, Michael, Liane Young, Ralph Adolphs, Daniel Tranel, Fiery Crushman, Marc Hauser, and Antonio Damasio. "Damage to the prefrontal cortex increases utilitarian moral judgements." Nature 486.908-911 (2007): n. pag. Web. 20 Mar 2010. <>.
5)Saletan, William. "Mind Makes Right: Brain Damage, Evolution, and the Future of Morality." Slate 31 March 2007: n. pag. Web. 21 Mar 2010. <>.
6)"Study Narrows Gap Between Mind and Brain." All Things Considered. NPR: 29 Mar 2010. Radio.
7)Wade, Nicholas. "Is ‘Do Unto Others’ Written Into Our Genes? ." New York Times 18 Sep 2007: n. pag. Web. 16 Mar 2010. <>.



Anonymous's picture


hello, i am a student in high school and i just read your article, i want to use it as a source for my essay on emotions and logic, can you tell me your name so I can properly cite it? thank you

aeraeber's picture


Sure. My name is Alexandra Raeber. Thank you for your interest.

Paul Grobstein's picture

Morality as a distributed system.

Motor patterns can involve both central pattern generators and reafferent loops.  Three dimensional vision involves conflict between two eyes, as well as ...  Interesting indeed to think about morality in this context.  Another distributed system, with conflict as not a problem but a virtue?  It might also be worth thinking a little more about "logic" and "emotion."  What exactly is the difference between the two?