The Interdisciplinary Study of Moral Issues Combining Philosophy with Cognitive science
date: Jan 7, 2019
Chao Liu (Professor, State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing)
figure1. Professor Chao Liu published a comment in Guangming Daily entitled “The Interdisciplinary Study of Moral Issues Combining Philosophy with Cognitive science”on January 7, 2019
As philosophy and cognitive science have differences in research ideas and research methods, the combination of philosophy and cognitive science means that problems and concepts shall be analyzed through conceptual analysis and logical derivation in philosophy, and then the problems and paradigms shall be selected and summarized from examples in the daily life for empirical research in cognitive science. From the perspective of philosophy, cognitive science can confirm or disconfirm philosophical viewpoints and thoughts empirically; in turn, the experimental evidence of cognitive science enables philosophy to redefine and analyze problems and concepts. More importantly, cognitive science provides an objective approach to solve the controversial issues facing the field of philosophy for many years that can only be expanded by subjective speculation.
One of the best examples of the joint research combining philosophy with cognitive science is the study in the area of morality. Morality is a general term of the Latin word for morals and the Greek word for ethics. It generally refers to the behavioral norms, manners and customs established by a social group. After centuries of evolvement, philosophical theory has adopted the logical analysis in the form of derivation, defining some universal principles in morality that can guide human behavior. On the other hand, cognitive science applies the scientific empirical research, concluding the major aspects of moral cognition on the basis of the changes in the moral behavior of patients with brain injury, and further elaborating the cognitive and neural mechanism of moral judgment and behavior. Philosophical theory can provide the study of morality based on cognitive science with customs and values that are general or applicable to specific cultures, while cognitive science can confirm the impact of these customs and values empirically and predict its future development, which allows philosophical theory to define and interpret morality. Therefore, philosophy and cognitive science can refer to and supplement each other for the study in the area of morality, which becomes the most fruitful area in terms of the joint research by philosophy and cognitive science. The following parts discuss how to combine philosophy with cognitive science to explore the topic together by taking three key issues facing the study in the area of morality-moral judgment, embodied moral emotions and machine morality as examples.
figure2. Early processing differences of three different emotions based on ERP (analysis in time-domain)
figure3. Early processing differences of three different emotions based on ERP (analysis in frequency-domain)
This is an ERP-based emotional research of three different emotions (guilt, shame, happiness). Based on analysis in time-domain and frequency-domain, we can know that Shame condition elicited larger P2 amplitudes over the frontal region than the guilt and happiness conditions did, and that guilt condition elicited larger alpha desynchronization over the left parietal region than the shame and happiness conditions did.
figure4. The application of fNIRS in the study of Interpersonal brain synchronization
figure5. Interpersonal brain synchronization differences in Face to Face and Face-blocked situations
In this study, we investigated how face-to-face interaction impacts interpersonal brain synchronization during two-person economic exchange by combining an economic exchange game paradigm with fNIRS hyperscanning. Pairs of strangers interacted repeatedly either face-to-face or face-blocked while their brain activations were simultaneously recorded in rTPJ (target region) and rDLPFC (control region). Through One-sample t-test of interpersonal brain synchronization, we found that CH5 and CH14 in the FF, CH19 in the FB condition showed significant synchronization. Our findings revealed that face-to-face interactions increased shared intentionality, the positive belief of cooperative decisions of each other and facilitated actual cooperation between partners compared to face-block interactions.
Moreover, the study of embodied cognition in moral emotions also proves the combination of philosophy and cognitive science is great. In the field of moral philosophy, metaphor is an important factor of morality embodiment as well as a process of language expression to describe the relationship between two objects or phenomena. One can directly replace the other in practical application in line with the relationship between these two objects or phenomena. One of the focuses of the study of moral metaphors is the relationship between physical cleanliness and moral purity, which is reflected in religious rituals and the daily life with different cultures. It can be clearly seen from the Macbeth effect in Shakespeare’s famous play-Macbeth. After Lady Macbeth persuaded Macbeth to murder King Duncan, she moaned with blood on her hands, “Wash it off. Damned spots! I’m going to wash it off!” Lady Macbeth hoped that she were able to shake off the feeling of guilt by washing off the spots of blood on her hands. This metaphor of “cleanliness as akin to holiness or virtue” makes people wish to achieve spiritual holiness by cleaning their bodies. Cognitive scientists further tested the moral metaphor through experiments. A study published in Science in 2006 by Zhong Chenbo and et al, indicated that recalling unethical events induces a need for cleaning the body and washing hands after recalling an unethical event can relieve feelings of guilt and regret. Meantime, through brain imaging technology, cognitive scientists demonstrated that watching cleaning products after unethical behaviors makes the sensory motor cortex in people’s brains extremely active, while cleaning after recalling immoral events could significantly reduce the activeness of brain areas related to emotions such as insula and medial prefrontal cortex. These studies in the area of cognitive science not only confirmed the connection between metaphor and embodied cognition in philosophical theories, but also further revealed the connection between cognition and brain mechanism, and elaborated how moral metaphor influence people’s moral emotions and behaviors with respect to the mechanism.
figure6. The changes of spontaneous brain activity before and after the cleaning/priming manipulation
In this study, we aimed to explore the neural mechanisms of actual physical cleaning compared to priming of cleaning concept through resting-state functional magnetic resonance imaging (fMRI). We measured the changes of spontaneous brain activity and brain network before and after the cleaning/priming manipulation following an unethical recall and report. Actual physical cleaning reduced the spontaneous brain activities in the right insula and MPFC, regions that involved in embodied moral emotion processing, while priming of cleaning decreased the spontaneous activities in the right SFG and right MFG, regions that activated in executive control tasks. The results support the embodied theory of morality.
Third, another challenging issue that requires philosophy and cognitive science to tackle and that relate to the future of humans is artificial intelligence and machine morality. In recent years, AlphaGo beats Lee Se-dol, which has created great mass fervor for studying artificial intelligence. How an intelligent machine can make correct moral judgments under the constraints of social norms created by humans has become a difficult issue for philosophers and cognitive scientists. For example, self-driving cars can effectively reduce the number of traffic accidents, but they must make a choice when they are faced with some extreme situations. In case of an emergency avoidance, there are only two choices: to hit the pedestrian or to sacrifice the vehicle and the passenger to save the pedestrian. What should self-driving cars do in this situation? People need to formulate an algorithm to guide the self-driving cars in making choices in case of similar circumstances. This kind of artificial setting involves specific moral and ethical issues, which cannot be resolved only by cognitive science without the participation of philosophers. In fact, philosophers have done a lot of researches on machine morality, explaining that researchers need to pay attention to two principles when faced with the dilemma: one is utilitarianism, which is to minimize the total harm to people; the other is the principle of self-protection, which gives more consideration to the safety of passengers in self-driving cars. The study published in Science in 2016 introduced that there is a dilemma in generating such a moral code, that is, people believe the principle of utilitarianism should be applied to guide self-driving cars in making decisions as it is more consistent with moral standards. However, passengers prefer the principle of self-protection, unwilling to buy and ride a self-driving car based on the principle of utilitarianism. In short, the development of artificial intelligence has brought a lot of opportunities and challenges to human society and the moral issues of artificial intelligence is what philosophers and cognitive scientists are extremely concerned with at present and in the future. Thinking from the philosophical point of view and the research from the perspective of cognitive science will provide the development of artificial intelligence with necessary guidance and suggestions.
The combination of philosophy and cognitive science for the research in the area of morality presents the two disciplines supplement each other and promote each other. The cross-platform construction of philosophy and cognitive science includes many aspects of the research on philosophy and cognitive science (cognitive neuroscience and philosophy, emotional brain, philosophy and ethics of artificial intelligence, etc.). Thus, it is believed that the interdisciplinary study of philosophy and cognitive science will flourish.
The link of articles：
• Tang, H.H., Lu, X.P., Su, R., Liang, Z.L., Mai, X.Q*., Liu, C*. (2017). Washing away your sins in the brain: Physical cleaning and priming of cleaning recruit different brain networks after moral threat. Social Cognitive & Affective Neuroscience.12(7):1149-1158 [PDF]
• Zhu, R.D., Wu, H.Y., Xu, Z.H., Tang, H.H., Shen, X.Y., Mai, X.Q*., Liu, C*. n(2017). Early Distinction between Shame and Guilt Processing in an Interpersonal Context. Social Neuroscience. [PDF]
• Tang, H.H., Mai, X.Q., Wang, S., Zhu. C.Z., Krueger, F., Liu, C *. (2016). Interpersonal brain synchronization in the right temporo-parietal junction during face-to-face economic exchange. Social Cognitive & Affective Neuroscience. 11(1):23-32 [PDF]