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Scientific progress may help us make breakthroughs in understanding the essence of human nature.The rapid and strong development of brain research in recent decades may indeed play such a role.Since ancient times,human beings have committed themselves to thinking about questions concerning the essence of human beings.This has gradually culminated in a number of common questions in the humanities,especially in philosophy.Recent development in the neurosciences is causing a rethinking or reawakening of these classic humanity questions,and even constitutes a challenge to the traditional answers of these questions.As scientists,we would like to sincerely share with our colleagues in the humanities our new view points and we also welcome their responses.In order to focus the discussion,we would like to present our points concerning three important issues in the humanity sciences： (I) The essence of the human mind,(Ⅱ) the conscious and unconscious brain,and (Ⅲ)and the question of whether we have free will.Our fundamental viewpoints are： the bodymind dualism should be explained by brainmonism; a major part of the brains working is unconscious mind/will; and free will in the common psychological sense does not exist.These view points may seem to be intense,but our goal is purely about the pursuit of truth,because that is the sole norm that scientists should pursue and follow.
Ⅰ. The Bodymind Dualism Should be Explained by Brainmonism
Since Descartes,philosophers have always been puzzled by the problem of dualism： mind and matter are two entirely different entities.How could objective (material) matter,during the last stage of the neuronal processing,zoom from the objective field into a completely different property field,i.e.the subjective field of the mind？How could objective things affect subjective things？The huge amount of literature on ″Philosophy of Mind″ which occupies a large proportion of todays philosophy seems immersed in the discussion of this question.As brain scientists,our answer to this issue is that the mind is not subjective,it is objective/matter.It is one of the properties of our brain,and is as objective as the other ″properties of objective things.″ Since the weight of evidence indicates that mental processes actually are processes of the brain,Descartes problem has disappeared,as Churchland (2008) rightly concluded［1］．
The mind is the result of our 100 billion brain cells working together,and is thus a product of the brain.The mind is produced by the brain by action potentials,neurotransmitters and synaptic changes,resulting in changes in activity of brain cells and interactions of brain areas.Other products of the brain are the regulation of body functions by the autonomic nervous system,motor behavior,and the release of hormones.From an anatomic point of view,the mind is the product of the ″extra″ brain tissue that we obtained during evolution on top of the brain tissue that we need to regulate those basic body functions.Therefore,not only mice, but also elephants and whales have (in spite of the fact that the latter two have larger brains than we) much less mind than we do［2］． Are the results of the brain work (experiences,mental states such as vision,pain,pleasure,happiness,colour red etc.) subjective？No, they are objective,since they are solely the consequence of the changes in transmitter release and activity of nerve cells in particular brain areas.For example,cone cells,the photoreceptor cells in the retina of the eye,respond to light of different wavelengths.The ″colour″ is coded in the electrical activity of the cones and decoded in the cortex.We see a red color because special cortical cells decode the code for the wavelength of red (colour).The basis of various mind activities is always a particular activity change of nerve cells and/or the communication of nerve cells with other particular brain areas.These brain activities are the production of our mind or qualitative experiences.These mental states can be introspected or expressed in language,while the bases of both introspection and language are objective (material).The modern neuroscientific technology can even enable us a thorough ″disenchantment″ (a term used by Max Weber) for the originally mysterious relationship between brain and mind.One can measure the working of the brain in an objective way by electrodes,HPLC,molecular techniques,microscopes,fMRI,and by behaviour.The increasingly precise fMRI (mindreading),electrophysiology (e.g.the brain cells that only electrically react when a picture of Bill Clinton is shown［34］),electrical stimulation or a release of a chemical messenger (dopamine in the nucleus accumbens gives a pleasant feeling),have been used to interpret mind action of the brain.Do these observations not illustrate that our mind is ″objective？″
If we regard the fact that the mind is produced by the brain as a ″general character,″ the fact that each subject possesses a unique mind due to his unique brain gives him an ″individual character.″ There are also good neuroscientific explanations for socalled ″subjective″ properties of ones personality or character.Factors of species,genetic background,differences in the environment during early brain development,and the remodelling of brain caused by the individuals later developmental circumstance or experiences,play together to make each brain different from each other［2］.Please note that because different individuals own different brains,they may even show the same behaviour based upon totally different intentions.Subject A feels empathy and wants to help other people, while subject B,due to a maldeveloped prefrontal cortex,does not feel empathy,but also helps other people in order to gain reputation and money for himself.These minddifferences can be explained on the basis of differences in brain structure and functions,so why would we call them ″subjective？″ Finally,we will give an interesting example that further supports our point of view that ″mind is material″： The 25yearold Matthew Nagle was completely paralyzed after having been stabbed in the neck.A 4×4mm plate with 96 electrodes was implanted in his motor cortex.The derived electrical activity of his brain cells that guide motor function enabled him to operate a computer.He learned to do this in just a few minutes timemerely by thinking about moving his hand and following a moving cursor on the computer screen.He also succeeded in drawing a circle on the screen,just by thinking about it,and to read his email,to play a computer game and even to open and close the fist of a prosthetic hand.This example indicates that thinking is the brains work that can be monitored by electrodes and translated into motor behaviour［5］.
In summary,current neuroscientific data indicate that brain and mind are both material,which implies that the socalled ″hard dualistic problem″ does in fact not exist and can be explained by brainmonism［1］.
Ⅱ. The Conscious and Unconscious Brain
Most of the Dualistic scholars make a clear distinction between the mind and material,since they believe that the mind,as one of brains characters,is essentially different from the other physical properties of the brain.For example,the mind must be aware or conscious.It should be noted,however,that most of our brains working is unconscious and that it can very well carry out tasks which were generally believed to require consciousness.Such unconscious processing of the brain is also one of its objective properties.
The brain,in many aspects,could be compared to a giant,unconscious computer,which can,to a very large degree,work on autopilot.We are continually bombarded by an enormous amount of information and unconsciously use selective attention to extract what is important to us.Many of our decisions are indeed made ″in a fraction of a second″ or ″instinctively,″ or on the basis of our ″intuition,″ or ″gut feelings″ without thinking about them consciously.We ″choose″ a partner by falling in love at first sight,and an accused man will tell the court in all sincerity that he killed the victim before he knew it.Just as todays planes can fly and land on autopilot without the assistance of a captain,our brain can,to a very great extent,function excellently without conscious thought.Of course our brain has to be trained to do this.It is only by feeding the unconscious brain a huge amount of data over a long period of time that an art expert reaches the stage of immediately ″sensing″ that hes looking at a forgery,and it is only by seeing a great number of patients that a medical specialist can develop the ″clinical glance″ that enables him/her to have made a diagnosis by the time a patient enters the room.Functional brain scanning has shown that we use different brain circuits for conscious reasoning and for making intuitive decisions.The products of conscious reasoning processes are by no means always superior to unconscious decisions.They can even get in the way of good decisions［2］. The material brain is indeed not provided with a higher task in this life.But the brain (= I) does have the unconscious wish ″to survive,″which has developed during evolution.Those organisms that did not strive to survive died out during the long course of evolution.It is an efficient mechanism that during evolution the wish for food and reproduction are strongly coupled to dopamine release in the Nucleus Accumbens,our rewarding centre.These basic wishes are sublimated in humans through products of work,science and art.Some people have this drive more than others (individual variability).It is mentionable that even the best computer,in contrast to a human brain,does not have the inherent wish to survive and to (re)produce.They are nonliving matter.
Ⅲ. Do We Have Free Will？
The discussion mentioned above is also related to another question,i.e.， is there a free will？Many people would insist that we do have free will.However,scientific experiments have implied that our brain makes decisions before we are conscious of such a decision.These observations seriously question whether we have any degree of free will.
As mentioned above,our overburdened brain constantly takes decisions by means of unconscious processes.Harvard psychologist Dan Wegner thus proposed to speak of an unconscious will,rather than a free will［67］.The unconscious will takes splitsecond decisions on the basis of what is going on in our surroundings,a process that is importantly determined by the way our brains were formed during development and by what we have learned since (=memories).The belief of ″free will″ comes partly from the feeling that we are constantly making free choices.According to Wegner,however,this is an illusion.He has carried out some experiments that support his theory.For instance person A stands in front of a mirror with his arms tucked out of sight.Person B stands behind him and stick his arms out under As armpits,where As arms would normally be.When Bs arms carry out commands that are given aloud by person C (such as ″scratch your nose,″ ″wave your right hand″),A gets the illusion that he is controlling these actions with his will.Wegners work clearly shows that both,the actions of Bs arm movements and the ″conscious″ idea of initiating an action (Bs arm movements) are prompted by unconscious processes in the brain of A.The ″conscious picture″ that As brain registers when B carries out an action gives A the feeling that he (=A) has knowingly performed that action.But,the fact is that there is no causal link between the brain events (feeling) in A and the arm movements of B.Therefore the feeling of A is an illusion. According to the Amsterdam psychologist Victor Lamme,the illusion of taking a conscious decision will only occur when the information on the action that is being performed is transmitted back to the cerebral cortex.The viewpoint that free will is simply an illusion is also supported by other experiments.Benjamin Libet showed in his famous experiments that when our bodies receive stimuli that are just above the threshold of awareness,there is half a seconds delay before our brains consciously register them.The same applies to actions initiated from the cerebral cortex.His conclusion that such actions are preceded by half a second of unconscious brain activity (visible as a ″readiness potential″) raised serious doubts as to the possibility of acting by free will［8］.Libets observations have been hotly debated,but recent experiments even show longer latencies.Fried studied individuals with electrodes implanted in their brains.Frieds experiments showed that there was activity in individual neurons of particular brain areas about a second and a half before the subject made a conscious decision to press a button.With about 700 milliseconds to go,the researchers could predict the timing of that decision with more than 80% accuracy［9］.In 2007,Haynes put people into a brain scanner (fMRI) in which there was a display screen on which a succession of random letters flashed［10］.The researchers told the subjects to press a button with either their right or left index fingers whenever they felt the urge,and to remember the letter that was showing on the screen when they made the decision.The fMRI revealed brain activity in real time as the volunteers chose to use their right or left hands.It was observed that the conscious decision to push the button was made about a second before the actual act,but the team discovered also that a pattern of brain activity seemed to predict that decision by as many as seven seconds.Long before the subjects were even aware of making a choice,their brains had already decided.Moreover,experiments have shown that consciousness lags behind the initiation of an action.In one such experiment,people were given the task of quickly touching a spot that lit up on a computer screen.Their visual cerebral cortexes worked with great speed.One tenth of a second after the light appeared,their brain fired off a message to the motor cerebral cortex to initiate the movement to touch the light.If the processing in the visual cerebral cortex was subsequently interrupted by a magnetic pulse,the action was carried out,but the person was not conscious of the screen lighting up［1112］. All these observations point to the same conclusion,i.e.，the notion that these actions are induced by free will is indeed illusory.The final answer to this important question,though,should come from future experiments.
Moreover,current knowledge of neurobiology shows that many inherited factors and environmental influences during early development affect the structure and functioning of our brains for the rest of our lives.This means that along with all kinds of potentials and talents,we have many builtin limitations,including a given level of aggression,our gender identity and our sexual orientation,and a greater or lesser tendency to develop ADHD,borderline personality disorder,depression or schizophrenia.In addition,we are born into a specific language area,which determines the structure and function of our brains to an important extent even though we have neither the ability to choose our mother tongue nor a geneticallybased aptitude for it.The religious environment into which we are born determines how we flesh out our innate spirituality,whether with faith,materialism or a profound concern for the environment［2］.
Ⅳ. Epilogue
We have presented our viewpoints concerning three important issues in the humanity sciences based upon progress in brain research.In general we think that the mind is objective,and that various factors determine each of our unique brains,which allows the brain to have individual property besides its general property of ″producing mind.″ Both properties are objective.In addition,we have pointed out that our brain has to work efficiently and unconsciously to make quick decisions.These unconscious decisions not only help to prove that our mind is objective,but also answer the question of ″conscious,free will.″
Furthermore,we think that the rapid development of neuroscience in recent decades not only promotes our exploration into the essence of human beings,but also significantly inspires our improving of social ethics and mechanisms.The notion that we are free to choose how to act is not only mistaken,but also has given rise to a great deal of misery.For instance,it used to be generally accepted that our sexual orientation,i.e.，heterosexuality,homosexuality or bisexuality,was a matter of choice,and given that all religions regard homosexuals as having made the wrong choice,homosexuality was,until recently,criminalized and regarded as an aberration.All kinds of attempts were made to ″cure″ homosexuals of their supposed disorder,none of which had the slightest effect.Neuroscience has shown,however,that before birth,structural irreversible brain differences are already formed in relation to genderidentity and sexual orientation［13］. In many countries,a person with a brain disorder who commits an offence for which he cannot be held accountable is not criminally liable.One generally agrees that in the case of a psychiatric disease free will cannot exist.The fact that prisoners have a very high prevalence of psychiatric disorders should raise serious concern in our society： how should our law deal with these people？How should we fairly and efficiently punish these offenders？
Bibliography
［1］ P.S.Churchland,″The Impact of Neuroscience on Philosophy,″Neuron,Vol.60,No.3(2008),pp.409411.
［2］ D.F.Swaab,We Are Our Brains： From the Womb to Alzheimers,trans.by Wang Yiyao,Chen Yanjing ＆ Bao Aimin,Beijing： China Renmin University Press,2011.
［3］ G.Kreiman,C.Koch ＆ I.Fried,″CategorySpecific Visual Responses of Single Neurons in the Human Medial Temporal Lobe,″National Neuroscience,Vol.3,No.9(2000),pp.946953.
［4］ G.Kreiman,C.Koch ＆ I.Fried,″Imagery Neurons in the Human Brain,″Nature,Vol.408,No.6810(2000),pp.357361.
［5］ L.R.Hochberg,M.D.Serruya ＆ G.M.Friehs et al.,″Neuronal Ensemble Control of Prosthetic Devices by a Human with Tetraplegia,″Nature,Vol.442,No.7099(2006),pp.164171.
［6］ D.M.Wegner,″The Minds Best Trick： How We Experience Conscious Will,″Trends in Cognitive Sciences,Vol.7,No.2(2003),pp.6569.
［7］ D.M.Wegner,″Precis of the Illusion of Conscious Will,″Behavioral and Brain Sciences,Vol.27,No.5(2004),pp.649692.
［8］ B.Libet,C.A.Gleason ＆ E.W.Wright et al.,″Time of Conscious Intention to Act in Relation to Onset of Cerebral Activity(ReadinessPotential)： The Unconscious Initiation of a Freely Voluntary Act,″Brain,Vol.106,No.3(1983),pp.623642.
［9］ I.Fried,R.Mukamel ＆ G.Kreiman,″Internally Generated Preactivation of Single Neurons in Human Medial Frontal Cortex Predicts Volition,″Neuron,Vol.69,No.3(2011),pp.548562.
［10］ C.S.Soon,M.Brass ＆ H.J.Heinze et al.,″Unconscious Determinants of Free Decisions in the Human Brain,″Nature Neuroscience,Vol.11,No.5(2008),pp.543545.
［11］ J.L.Boyer,S.Harrison,＆ T.Ro,″Unconscious Processing of Orientation and Color without Primary Visual Cortex,″Proceedings of the National Academy of Science USA,Vol.102,No.46(2005),pp.1687516879.
［12］ T.Ro,D.Shelton ＆ O.L.Lee et al.,″Extrageniculate Mediation of Unconscious Vision in Transcranial Magnetic StimulationInduced Blindsight,″Proceedings of the National Academy of Science USA,Vol.101,No.26(2004),pp.99339935.
［13 ］ A.Bao ＆ D.F.Swaab,″Sex Differences in the Brain,Behavior,and Neuropsychiatric Disorders,″Neuroscientist,Vol.16,No.5 (2010),pp.550565. Received date: 20120326
Website: http://www.journals.zju.edu.cn/soc
Online first date: 20120703
Authou profile: 1.Bao Aimin,a professor of Zhejiang University School of Medicine, is engaged in study of neurobiology and pathogenesis of neuropsychiatric diseases； 2.Luo Jianhong, a professor of Zhejiang University School of Medicine, is engaged in study of molecular and cellular mechanisms of synaptic function； 3.Professor Dick Swaab is an internationally renowned researcher in neuroscience, who received numerous awards and published over 500 scientific papers.He served as director of the Netherlands Institute for Brain Research for 27 years.Currently, he is also a leader of the Neuropsychiatric Disorders research team at the Netherlands Institute of Neuroscience and his main research interests include sexual differentiation of the brain, neurodegenerative disorders and depression.In 2008, Professor Dick F.Swaab received the Academy medal for his significant role in national and international neuroscience.
Ⅰ. The Bodymind Dualism Should be Explained by Brainmonism
Since Descartes,philosophers have always been puzzled by the problem of dualism： mind and matter are two entirely different entities.How could objective (material) matter,during the last stage of the neuronal processing,zoom from the objective field into a completely different property field,i.e.the subjective field of the mind？How could objective things affect subjective things？The huge amount of literature on ″Philosophy of Mind″ which occupies a large proportion of todays philosophy seems immersed in the discussion of this question.As brain scientists,our answer to this issue is that the mind is not subjective,it is objective/matter.It is one of the properties of our brain,and is as objective as the other ″properties of objective things.″ Since the weight of evidence indicates that mental processes actually are processes of the brain,Descartes problem has disappeared,as Churchland (2008) rightly concluded［1］．
The mind is the result of our 100 billion brain cells working together,and is thus a product of the brain.The mind is produced by the brain by action potentials,neurotransmitters and synaptic changes,resulting in changes in activity of brain cells and interactions of brain areas.Other products of the brain are the regulation of body functions by the autonomic nervous system,motor behavior,and the release of hormones.From an anatomic point of view,the mind is the product of the ″extra″ brain tissue that we obtained during evolution on top of the brain tissue that we need to regulate those basic body functions.Therefore,not only mice, but also elephants and whales have (in spite of the fact that the latter two have larger brains than we) much less mind than we do［2］． Are the results of the brain work (experiences,mental states such as vision,pain,pleasure,happiness,colour red etc.) subjective？No, they are objective,since they are solely the consequence of the changes in transmitter release and activity of nerve cells in particular brain areas.For example,cone cells,the photoreceptor cells in the retina of the eye,respond to light of different wavelengths.The ″colour″ is coded in the electrical activity of the cones and decoded in the cortex.We see a red color because special cortical cells decode the code for the wavelength of red (colour).The basis of various mind activities is always a particular activity change of nerve cells and/or the communication of nerve cells with other particular brain areas.These brain activities are the production of our mind or qualitative experiences.These mental states can be introspected or expressed in language,while the bases of both introspection and language are objective (material).The modern neuroscientific technology can even enable us a thorough ″disenchantment″ (a term used by Max Weber) for the originally mysterious relationship between brain and mind.One can measure the working of the brain in an objective way by electrodes,HPLC,molecular techniques,microscopes,fMRI,and by behaviour.The increasingly precise fMRI (mindreading),electrophysiology (e.g.the brain cells that only electrically react when a picture of Bill Clinton is shown［34］),electrical stimulation or a release of a chemical messenger (dopamine in the nucleus accumbens gives a pleasant feeling),have been used to interpret mind action of the brain.Do these observations not illustrate that our mind is ″objective？″
If we regard the fact that the mind is produced by the brain as a ″general character,″ the fact that each subject possesses a unique mind due to his unique brain gives him an ″individual character.″ There are also good neuroscientific explanations for socalled ″subjective″ properties of ones personality or character.Factors of species,genetic background,differences in the environment during early brain development,and the remodelling of brain caused by the individuals later developmental circumstance or experiences,play together to make each brain different from each other［2］.Please note that because different individuals own different brains,they may even show the same behaviour based upon totally different intentions.Subject A feels empathy and wants to help other people, while subject B,due to a maldeveloped prefrontal cortex,does not feel empathy,but also helps other people in order to gain reputation and money for himself.These minddifferences can be explained on the basis of differences in brain structure and functions,so why would we call them ″subjective？″ Finally,we will give an interesting example that further supports our point of view that ″mind is material″： The 25yearold Matthew Nagle was completely paralyzed after having been stabbed in the neck.A 4×4mm plate with 96 electrodes was implanted in his motor cortex.The derived electrical activity of his brain cells that guide motor function enabled him to operate a computer.He learned to do this in just a few minutes timemerely by thinking about moving his hand and following a moving cursor on the computer screen.He also succeeded in drawing a circle on the screen,just by thinking about it,and to read his email,to play a computer game and even to open and close the fist of a prosthetic hand.This example indicates that thinking is the brains work that can be monitored by electrodes and translated into motor behaviour［5］.
In summary,current neuroscientific data indicate that brain and mind are both material,which implies that the socalled ″hard dualistic problem″ does in fact not exist and can be explained by brainmonism［1］.
Ⅱ. The Conscious and Unconscious Brain
Most of the Dualistic scholars make a clear distinction between the mind and material,since they believe that the mind,as one of brains characters,is essentially different from the other physical properties of the brain.For example,the mind must be aware or conscious.It should be noted,however,that most of our brains working is unconscious and that it can very well carry out tasks which were generally believed to require consciousness.Such unconscious processing of the brain is also one of its objective properties.
The brain,in many aspects,could be compared to a giant,unconscious computer,which can,to a very large degree,work on autopilot.We are continually bombarded by an enormous amount of information and unconsciously use selective attention to extract what is important to us.Many of our decisions are indeed made ″in a fraction of a second″ or ″instinctively,″ or on the basis of our ″intuition,″ or ″gut feelings″ without thinking about them consciously.We ″choose″ a partner by falling in love at first sight,and an accused man will tell the court in all sincerity that he killed the victim before he knew it.Just as todays planes can fly and land on autopilot without the assistance of a captain,our brain can,to a very great extent,function excellently without conscious thought.Of course our brain has to be trained to do this.It is only by feeding the unconscious brain a huge amount of data over a long period of time that an art expert reaches the stage of immediately ″sensing″ that hes looking at a forgery,and it is only by seeing a great number of patients that a medical specialist can develop the ″clinical glance″ that enables him/her to have made a diagnosis by the time a patient enters the room.Functional brain scanning has shown that we use different brain circuits for conscious reasoning and for making intuitive decisions.The products of conscious reasoning processes are by no means always superior to unconscious decisions.They can even get in the way of good decisions［2］. The material brain is indeed not provided with a higher task in this life.But the brain (= I) does have the unconscious wish ″to survive,″which has developed during evolution.Those organisms that did not strive to survive died out during the long course of evolution.It is an efficient mechanism that during evolution the wish for food and reproduction are strongly coupled to dopamine release in the Nucleus Accumbens,our rewarding centre.These basic wishes are sublimated in humans through products of work,science and art.Some people have this drive more than others (individual variability).It is mentionable that even the best computer,in contrast to a human brain,does not have the inherent wish to survive and to (re)produce.They are nonliving matter.
Ⅲ. Do We Have Free Will？
The discussion mentioned above is also related to another question,i.e.， is there a free will？Many people would insist that we do have free will.However,scientific experiments have implied that our brain makes decisions before we are conscious of such a decision.These observations seriously question whether we have any degree of free will.
As mentioned above,our overburdened brain constantly takes decisions by means of unconscious processes.Harvard psychologist Dan Wegner thus proposed to speak of an unconscious will,rather than a free will［67］.The unconscious will takes splitsecond decisions on the basis of what is going on in our surroundings,a process that is importantly determined by the way our brains were formed during development and by what we have learned since (=memories).The belief of ″free will″ comes partly from the feeling that we are constantly making free choices.According to Wegner,however,this is an illusion.He has carried out some experiments that support his theory.For instance person A stands in front of a mirror with his arms tucked out of sight.Person B stands behind him and stick his arms out under As armpits,where As arms would normally be.When Bs arms carry out commands that are given aloud by person C (such as ″scratch your nose,″ ″wave your right hand″),A gets the illusion that he is controlling these actions with his will.Wegners work clearly shows that both,the actions of Bs arm movements and the ″conscious″ idea of initiating an action (Bs arm movements) are prompted by unconscious processes in the brain of A.The ″conscious picture″ that As brain registers when B carries out an action gives A the feeling that he (=A) has knowingly performed that action.But,the fact is that there is no causal link between the brain events (feeling) in A and the arm movements of B.Therefore the feeling of A is an illusion. According to the Amsterdam psychologist Victor Lamme,the illusion of taking a conscious decision will only occur when the information on the action that is being performed is transmitted back to the cerebral cortex.The viewpoint that free will is simply an illusion is also supported by other experiments.Benjamin Libet showed in his famous experiments that when our bodies receive stimuli that are just above the threshold of awareness,there is half a seconds delay before our brains consciously register them.The same applies to actions initiated from the cerebral cortex.His conclusion that such actions are preceded by half a second of unconscious brain activity (visible as a ″readiness potential″) raised serious doubts as to the possibility of acting by free will［8］.Libets observations have been hotly debated,but recent experiments even show longer latencies.Fried studied individuals with electrodes implanted in their brains.Frieds experiments showed that there was activity in individual neurons of particular brain areas about a second and a half before the subject made a conscious decision to press a button.With about 700 milliseconds to go,the researchers could predict the timing of that decision with more than 80% accuracy［9］.In 2007,Haynes put people into a brain scanner (fMRI) in which there was a display screen on which a succession of random letters flashed［10］.The researchers told the subjects to press a button with either their right or left index fingers whenever they felt the urge,and to remember the letter that was showing on the screen when they made the decision.The fMRI revealed brain activity in real time as the volunteers chose to use their right or left hands.It was observed that the conscious decision to push the button was made about a second before the actual act,but the team discovered also that a pattern of brain activity seemed to predict that decision by as many as seven seconds.Long before the subjects were even aware of making a choice,their brains had already decided.Moreover,experiments have shown that consciousness lags behind the initiation of an action.In one such experiment,people were given the task of quickly touching a spot that lit up on a computer screen.Their visual cerebral cortexes worked with great speed.One tenth of a second after the light appeared,their brain fired off a message to the motor cerebral cortex to initiate the movement to touch the light.If the processing in the visual cerebral cortex was subsequently interrupted by a magnetic pulse,the action was carried out,but the person was not conscious of the screen lighting up［1112］. All these observations point to the same conclusion,i.e.，the notion that these actions are induced by free will is indeed illusory.The final answer to this important question,though,should come from future experiments.
Moreover,current knowledge of neurobiology shows that many inherited factors and environmental influences during early development affect the structure and functioning of our brains for the rest of our lives.This means that along with all kinds of potentials and talents,we have many builtin limitations,including a given level of aggression,our gender identity and our sexual orientation,and a greater or lesser tendency to develop ADHD,borderline personality disorder,depression or schizophrenia.In addition,we are born into a specific language area,which determines the structure and function of our brains to an important extent even though we have neither the ability to choose our mother tongue nor a geneticallybased aptitude for it.The religious environment into which we are born determines how we flesh out our innate spirituality,whether with faith,materialism or a profound concern for the environment［2］.
Ⅳ. Epilogue
We have presented our viewpoints concerning three important issues in the humanity sciences based upon progress in brain research.In general we think that the mind is objective,and that various factors determine each of our unique brains,which allows the brain to have individual property besides its general property of ″producing mind.″ Both properties are objective.In addition,we have pointed out that our brain has to work efficiently and unconsciously to make quick decisions.These unconscious decisions not only help to prove that our mind is objective,but also answer the question of ″conscious,free will.″
Furthermore,we think that the rapid development of neuroscience in recent decades not only promotes our exploration into the essence of human beings,but also significantly inspires our improving of social ethics and mechanisms.The notion that we are free to choose how to act is not only mistaken,but also has given rise to a great deal of misery.For instance,it used to be generally accepted that our sexual orientation,i.e.，heterosexuality,homosexuality or bisexuality,was a matter of choice,and given that all religions regard homosexuals as having made the wrong choice,homosexuality was,until recently,criminalized and regarded as an aberration.All kinds of attempts were made to ″cure″ homosexuals of their supposed disorder,none of which had the slightest effect.Neuroscience has shown,however,that before birth,structural irreversible brain differences are already formed in relation to genderidentity and sexual orientation［13］. In many countries,a person with a brain disorder who commits an offence for which he cannot be held accountable is not criminally liable.One generally agrees that in the case of a psychiatric disease free will cannot exist.The fact that prisoners have a very high prevalence of psychiatric disorders should raise serious concern in our society： how should our law deal with these people？How should we fairly and efficiently punish these offenders？
Bibliography
［1］ P.S.Churchland,″The Impact of Neuroscience on Philosophy,″Neuron,Vol.60,No.3(2008),pp.409411.
［2］ D.F.Swaab,We Are Our Brains： From the Womb to Alzheimers,trans.by Wang Yiyao,Chen Yanjing ＆ Bao Aimin,Beijing： China Renmin University Press,2011.
［3］ G.Kreiman,C.Koch ＆ I.Fried,″CategorySpecific Visual Responses of Single Neurons in the Human Medial Temporal Lobe,″National Neuroscience,Vol.3,No.9(2000),pp.946953.
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Website: http://www.journals.zju.edu.cn/soc
Online first date: 20120703
Authou profile: 1.Bao Aimin,a professor of Zhejiang University School of Medicine, is engaged in study of neurobiology and pathogenesis of neuropsychiatric diseases； 2.Luo Jianhong, a professor of Zhejiang University School of Medicine, is engaged in study of molecular and cellular mechanisms of synaptic function； 3.Professor Dick Swaab is an internationally renowned researcher in neuroscience, who received numerous awards and published over 500 scientific papers.He served as director of the Netherlands Institute for Brain Research for 27 years.Currently, he is also a leader of the Neuropsychiatric Disorders research team at the Netherlands Institute of Neuroscience and his main research interests include sexual differentiation of the brain, neurodegenerative disorders and depression.In 2008, Professor Dick F.Swaab received the Academy medal for his significant role in national and international neuroscience.