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The trend in the literature on fetal pain is to approach the question of consciousness in the fetus in terms of conscious states of pain. That is, first define what makes a pain a conscious mental state, and then determine being a conscious fetus in terms of having such a state. Thus, the possibility of a conscious fetus is thought to rely on theories of conscious pain states. Call this the state approach to fetal pain. 

Two state approaches to fetal pain are present in the literature. One approach looks at the brain structure(s), pathways and circuits necessary for conscious pain states and then seeks to establish whether this substrate is present and functional in the fetus. There is broad agreement among researchers that the minimal necessary neural pathways for pain are in the human fetus by 24 weeks gestation [1, for review]. Some researchers argue that the fetus can feel pain earlier than 24 weeks because pain is enabled by subcortical brain structures [4,5,6].

Another phenomenal approach is to consider the subjective content of a conscious experience of pain, and to ask whether that content might be available to the fetus [1,2,3]. Based on this approach, some researchers argue that the fetus cannot feel pain at any stage because it lacks developmental abilities and concepts such as sense of self necessary for pain [1,2,3].

Although both state approaches are presented as opposites in the literature, they share the determination of fetal pain based on specific levels or degrees of complexity, whether of the brain structures and the relationship they have to the conscious state of pain, or of the subjective contents that constitute that state.

An alternate approach to understanding fetal consciousness that has not been explored in the literature on fetal pain is the extent to which pain is based on the arrangement of certain brain structures (or experiential contents), rather than a result of maturation or increase in complexity achieved by growth of the brain substrate which below a certain size does not enable consciousness [7,8]. Thus, whether the fetus is excluded in this regard is not due to its simplicity, but because its lack of certain brain arrangements necessary to enable consciousness.

According to this alternate view of fetal pain, a living creature’s subjective contents may differ greatly in complexity. To convey the range of conscious possibilities, consider the Indian ‘scale of sentience’ (cited in [8]):

‘This.’
‘This is so.’
‘I am affected by this which is so.’
‘So this is I who am affected by this which is so.’

The possibilities in this consciousness scale range from simply experienced sensation (‘This’; ‘This is so’) to self-consciousness (‘I am affected by this which is so’; ‘So this is I who am affected by this which is so’). Each stage in this scale presupposes consciousness. Any experience, whatever its degree of complexity, is conscious. It follows that to see, to hear, and to feel is to be conscious, irrespective of whether in addition a creature is self-conscious that it is seeing, hearing, and feeling [7]. To feel pain is to be conscious of that experience regardless of whether in addition one is self-conscious of being in pain. Self-consciousness is just one of many contents of consciousness available to big-brained living creatures with complex capacities: it is not definitive of consciousness [7,8]. The point of saying this is that it circumvents the logical mistake of misidentifying attributes unique to a specialized form of consciousness (e.g., self-consciousness) as general features of consciousness itself.

With this alternate view of consciousness now sketched in, we should determine where the fetus and where pain fall in the Indian scale of sentience. The possibilities in the scale extend from mere sensation to self-consciousness–where does the fetus fall in?

References

[1] Derbyshire S, Raja A. (2011). On the development of painful experience.Journal of Consciousness Studies18, 9–10.

[2] Derbyshire SW. (2006). Controversy: Can fetuses feel pain?. BMJ: British Medical Journal332(7546), 909.

[3] Szawarski Z. (1996). Do fetuses feel pain? Probably no pain in the absence of “self”. BMJ: British Medical Journal313(7060), 796–797.

[4] Anand KJ, Hickey PR. (1987). Pain and its effects in the human neonate and fetus. New England Journal of Medicine317(21), 1321–1329.

[5] Anand KJ. (2007). Consciousness, cortical function, and pain perception in nonverbal humans. Behavioral and Brain Sciences30(01), 82–83.

[6] Lowery CL, Hardman MP, Manning N, Clancy B, Whit Hall R, Anand KJS. (2007). Neurodevelopmental changes of fetal pain. In Seminars in perinatology (Vol. 31, No. 5, pp. 275–282).

[7] Merker B. (1997). The common denominator of conscious states: Implications for the biology of consciousness. Available at: http://cogprints.soton.ac.uk.

[8] Merker B. (2007). Consciousness without a cerebral cortex, a challenge
for neuroscience and medicine. Target article with peer commentary and author’s response. Behavioral and Brain Sciences, 30, 63–134.

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The University of Tokyo Center for Philosophy, Uehiro Research Division,
Philosophy of Disability & Co-existence Project (UTCP/PhDC):

3rd International Conference ‘Phenomenology of Pain’

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Brad Sloan

In this first post of a series, I describe and challenge several criticisms of reductive materialism, or mind-brain identity theory [5,6,7,8,9,10], made by psychologist Max Velmans. My focus in this post concerns Velmans’s arguments against mind-brain identity theory as presented in ‘What non-eliminative materialism needs to show’ in Appendix I of [4]. Future posts will address his other arguments against mind-brain identity theory as presented in the same work. My intention here is not simply negative, but also positive: using the first-person third-person distinction Velmans appeals to, I propose that the first-person point of view (introspection) and first-person methods are necessary to consciousness science. In developing this view, I focus mostly on pain.

Velmans is a long-time critic of materialist theories of phenomenal consciousness [1,2,3,4]. Following philosopher CD Broad, Velmans distinguishes three versions of materialism: radical, reductive and emergent. He writes [4]:

Radical materialism claims that the term “consciousness” does not refer to anything real (in contemporary philosophy this position is usually called “eliminativism”). Reductive materialism accepts that consciousness does refer to something real, but science will discover that real thing to be nothing more than a state (or function) of the brain. Emergentism also accepts the reality of consciousness but claims it to be a higher-order property of brains; it supervenes on neural activity, but cannot be reduced to it. [4,20]

Velmans begins his argument against mind-body identity theory:

Let us assume that, in some sense, our conscious experiences are real. To each and every one of us, our conscious experiences are observable phenomena (psychological data) which we can describe with varying degrees of accuracy in ordinary language. Other people’s experiences might be hypothetical constructs, as we cannot observe their experiences in the direct way that we can observe our own, but that does not make our own experiences similarly hypothetical. Nor are our own conscious experiences “theories” or “folk psychologies.” We may have everyday theories about what we experience, and with deeper insight, we might be able to improve them, but this would not replace, or necessarily improve the experiences themselves. [4,20-21]

In this passage, Velmans denies that our conscious experiences are ‘theories’ or ‘folk psychologies.’ However, since that is a central claim made by radical materialism (‘eliminativism’) [5,6], not reductive materialism (mind-brain identity theory), Velmans is in error to attribute it to the latter. Like mind-brain identity theory, eliminativism accepts the claim that conscious states are ‘nothing over and above’ brain states (minimal reductionism), but it rejects type identity. This is because eliminativism denies that conscious states are real, and do not exist [10]. By contrast, mind-brain identity theory is realist about mental states and experiences [10]. Mind-brain identity theory is not equivalent to eliminativism [10] (1).

The final sentence in the quote above reads: ‘We may have everyday theories about what we experience, and with deeper insight, we might be able to improve them, but this would not replace, or necessarily improve the experiences themselves.'[my italics] Critics of mind-brain identity theory, like Velmans, believe that a successful scientific reduction of consciousness would make all conscious experiences somehow unreal or even disappear [e.g., 17,18]. Using this conception of reduction, it is then reasoned that because it is observably obvious that a conscious experience like pain is real, it cannot be reduced by science to neurobiological mechanism. This misunderstanding trades on a peculiar view of reduction, where it is expected that in science, type identity claims make conscious experiences disappear. I think this expectation is incorrect.

Temperature was ontologically reduced to mean molecular kinetic energy, but no person expects that temperature therefore ceased to be real or became scientifically disrespectable or redundant. Visible light was ontologically reduced to electromagnetic radiation, but light did not disappear. Instead, scientists understand more about the real nature of light than they did before 1873. Light is real, no doubt; and so is temperature. Some expectations about the nature of temperature and light did change, and scientific progress does occasionally require rethinking what was believed about phenomenon. In certain instances, previously respectable states and substances sometimes did prove to be unreal. The caloric theory of heat did not survive rigorous experimental testing; caloric fluid thus proved to be unreal. Thus, a successful type identity of pain with mechanism means only that there is an explanation of pain. It is a reduction. But, scientific explanations of phenomenon do not typically make them disappear [5,6,10].

Velmans continues his argument:

In essence then, the claim that conscious experiences are nothing more than brain states is a claim about one set of phenomena (first-person experiences of love, hate, the smell of mown grass, the colour of a sunset, etc.) being nothing more than another set of phenomena (brain states, viewed from the perspective of an external observer). Given the extensive, apparent differences between conscious experiences and brain states this is a tall order. [4,21]

By characterizing mind-brain identity theory as a ‘tall order’, Velmans is in danger of begging the question. It is possible that science will never understand how brain structures such as neurons and protein channels produce pains, emotions and thoughts. The reality of the brain may be forever closed to us. Still, that the problem of consciousness is scientifically tractable or intractable, solvable or insolvable, is impossible to tell simply by noting appearances, since problems do not rank level of difficulty on their sleeves. Why should the problem of consciousness be any different?

Besides, things change. Over time, the nature of a problem may alter shape as new knowledge and understanding arrive. A problem may come to be viewed in novel ways as a result of reciprocal developments in technology, scientific methods and theory. For example, the composition of stars was regarded by scientists as an intractable problem. The problem was that it was impossible to get close enough to collect a star sample without burning up. However, with the unexpected discovery of spectral analysis, this problem proved tractable. The elements of stars were found to produce a type of fingerprint when heated to incandescence, easily observed when light produced from a source is passed through a prism.

In the early twentieth century, the copying problem in molecular genetics was thought to be intractable. This problem, however, was solved in the decades following Watson and Crick’s 1953 publication that DNA is a double helix. By contrast, the problem of how protein molecules fold into their 3D shape once made, believed by many scientists to be solvable in the mid-twentieth century, remains entirely unsolved today despite many decades of effort. Moreover, contributing solutions to twenty-first century problems can come from surprising and novel sources that may challenge conventional thinking. What seems apparently true or observably obvious during immediate experience or armchair reflection is sometimes a poor guide to reality.

Velmans again:

Instances where phenomena viewed from one perspective turned out to be one and the same as seemingly different phenomena viewed from another perspective do occur in the history of science. A classical example is the way the “morning star” and the “evening star” turned out to be identical (they were both found to be the planet Venus). But viewing consciousness from a first- versus a third-person perspective is very different to seeing the same planet in the morning or the evening. From a third-person (external observer’s) perspective one has no direct access to a subject’s conscious experience. Consequently, one has no third-person data (about the experience itself) which can be compared to or contrasted with the subject’s first-person data. [4,21]

It is unclear what Velmans means by ‘From a third-person (external observer’s) perspective one has no direct access to a subject’s conscious experience.’ I presume he intends that what I experience during a conscious episode cannot be available to you or indeed any one else in the way it is directly available to me. I occupy a uniquely privileged position concerning my experience that no one else can occupy. But if so, then he is intuitively characterizing the problem of consciousness in terms of method of access, and in terms of a privileged mode of access at that, namely, ‘direct’ personal introspection, which is question-begging.

This intuitive take on the problem of consciousness also results in a misrepresentation of what science is really up to, since the scientific enterprise relies on the intersubjective availability of its subject matter, in that no one is privileged with regard to collecting evidence about the object of the study. This means that no one has any special epistemic authority over evidence that others cannot in principle understand. In principle, must a successful reduction of pain produce a scientific explanation and pain? Obviously, no – scientific pain research aims to explain pain; it is not in the business of spontaneously concocting the phenomenon in question. To think otherwise is to misrepresent the limits and possibilities of science [5,6,10].

Now, there is a positive characterization of Velmans’s appeal to the first-person and third-person distinction I wish to show. Velmans’s description of the consciousness landscape should be taken to imply that the subject matter of consciousness research is brain mechanism as related to conscious phenomena. For example, the subject of pain science is brain mechanism as related to pain phenomena (e.g., acute pain, chronic pain, fetal pain, empathy for pain, dreamed pain, near-death pain, and so on). Consciousness research aims to discover the brain mechanisms subserving conscious experiences accessible only through introspection, which means that consciousness research is entirely reliant on the first-person point of view and on using first-person investigative methods. Contrary to Velmans’s view, this necessarily includes introspection together with third-person methods (e.g., neuroimaging). Since consciousness research aims to know which experience types are generated by which brain mechanism, researchers must naturally know when specific conscious experiences occur and what their personal qualities are. Which means that introspection is indispensable to consciousness research.

The history of scientific pain research clearly shows that introspection has been extensively used. For example, pain psychophysics typically uses subject pain verbal-report or non-verbal behavior (e.g., facial expressions) to infer the presence of pain. That is, pain psychophysics is committed to subject introspection. It is also important to remember that the validity of pain-related neuroimaging was established by the correlation of brain images with self-report of pain [19].

Finally, Velmans:

Neurophysiological investigations are limited, in principle, to isolating the neural correlates or antecedent causes of given experiences. This would be a major scientific advance. But what would it tell us about the nature of consciousness itself? [4,21]

I will respond to Velmans’s question with my own: how is mind-brain identity theory positioned relative to the indispensability of introspection to consciousness research? As Velmans notes, introspection is a direct way of coming to know about personal experiences and their qualities. It is an epistemological activity. Still, despite appearances to the contrary or personal conviction, what introspection reveals to us may be utterly mechanistic. It may be that what neuroscientists study through third-person methods is type identical with what is personally experienced through introspection, that is, brain mechanisms of the appropriate type. There is only one type of activity in question: the brain mechanism with all and only physical properties.

Mind-brain identity theory follows a long line of identifications that have marked progress in knowledge: water is H2O, light is electromagnetic energy, lightning is electrical discharge, influenza is a viral infection, and so on. Each of these identities is part of a larger theory that was accepted because it provided a better explanation of the evidence than rival theories. To illustrate this claim, take the conventional example of the type identity of fire and rapid oxidation. Why is this type identification descriptive (i.e., informative)? The first step is to conduct a qualitative investigation of fire. The flame is the visible part of fire, it releases heat and light, is normally sustained by a continuous supply of fuel, and so on. Some qualitative facts about fire are easily observed and others take further investigation, for instance, facts about the reactions that make fire explode. This provides a provisional description of fire. These qualitative descriptions (facts) about fire are then matched with qualitative descriptions (facts) about the operation of rapid oxidation, which is the sequence of chemical reactions between a fuel and an oxidant, such as oxygen or fluorine gas. These facts are harder to describe but essential. When sufficient information is at hand concerning the parts and operations of fire and the parts and operations of specific chemical reactions (rapid oxidation), we can describe how the structure of fire delineates its qualitative chemical properties. The multilevel mechanistic description of fire type identifies it with a specific mechanism type, rapid oxidation, and describes its behavior in terms of the behavior and composition of this mechanical operation. Fire is rapid oxidation.

The type identification of fire and rapid oxidation is only enabled if other substances are also type identified with other molecules, and if elements are type identified with chemical types, and so on. That is, the type identity of fire and rapid oxidation works because it is framed in the broader descriptive context of chemistry and physics. Those general framework theories imply the type identifications. Of course, the type identification of fire and rapid oxidation might be faulted as an incorrect description, perhaps because the physical operations involve activity in a broader range of physical processes. But that criticism merely asserts a different type identity description, and does not challenge type identity claims per se. It is conceivable to ponder whether fire is correctly type identified with rapid oxidation rather than with some other operation; but within the framework of chemistry and physics as they are understood, it is not reasonable to ponder whether fire might fail to be any type of mechanical operation at all.

In the same way, mind-brain identity theory is part of a rich theory that aims to explain conscious and unconscious mental phenomena such as perception, memory, reasoning, addiction, and disease. The personal experience of pain is multidimensional and involves specific sensory, emotional and cognitive features. I think there is a well established multilevel view of the physiological mechanisms that best describes pain qualities. This mechanistic description is framed within the context of advancing theories of the nervous, endocrine and immune systems and their complex functional interdependencies. There are also complex adaptive system-based descriptions of pain experience. Taken together, these descriptions reveal how pain is type identified with mechanism [10].

Although empirical progress in the understanding of pain is typically gradual and piecemeal, the type identification of pain with brain mechanism does not proceed in an additive manner. Pain scientists do not discover one pain type identity at a time and then add them together. Rather, what justifies claims to have type identified the mechanisms of pain is the way the entire multilevel mechanistic package coheres [10].

Endnotes

1. Briefly, the central argument for eliminativism is the idea that we use a theoretical framework to explain and predict human behavior [11], usually called the theory-theory (TT). TT views folk psychology (FP) as comprising specific theoretical claims and generalizations (and laws), described by our everyday common-sense psychological (i.e., mental) words such as ‘belief’, ‘desire’, ‘recognition’, ‘fear’, ‘anticipate’, ‘memory’ or ‘pain’. FP generalizations are thought to describe the diverse causal regularities and relations of FP claims.

TT claims that FP generalizations and claims operate in FP much like the generalizations and laws of scientific theories. However, the laws of FP are acquired more informally than scientific theories, as part of normal human development [e.g., 12,13,14,15]. For example, children who observe their parents showing fear and behavioral avoidance to back-stressing tasks, such as lifting heavy objects, may adjust their understanding of that situation (‘back-stressing tasks are dangerous and can cause pain’) and the behavioral effects (‘avoidance of back-stressing tasks generally reduces pain’) based on the generalization ‘Since back-stressing tasks can cause pain, and avoidance of these tasks generally reduces pain, it is best to avoid such tasks’ [16].

References

[1] Velmans, M. (2000). Understanding Consciousness. London: Routledge/Psychology Press.

[2] Velmans M. (2001a). A natural account of phenomenal consciousness. Consciousness and Communication, 34(1&2), 39-59.

[3] Velmans M. (2001b). Heterophenomenology versus critical phenomenology: A dialogue with Dan Dennett. http://cogprints.soton.ac.uk/documents/disk0/00/00/17/95/index.html.

[4] Velmans M. (2002). How Could Conscious Experiences Affect Brains? Journal of Consciousness Studies 9(11), 3-29.

[5] Churchland PM. (2007). Neurophilosophy at work. Cambridge, UK: Cambridge University Press.

[6] Churchland PS. (1989). Neurophilosophy: Toward a unified science of the mind-brain. Cambridge, Mass.: The MIT Press.

[7] Place UT. (1956). Is Consciousness a Brain Process? British Journal of Psychology47, 44-50.

[8] Polger TW. (2004). Natural minds. Cambridge, Mass.: The MIT Press.

[9] Smart JJC. (1959).  Sensations and Brain Processes. Philosophical Review68, 141-156.

[10] van Rysewyk S. (2013). Pain is Mechanism. PhD Dissertation, University of Tasmania.

[11] Sellars W. (1956). Empiricism and the Philosophy of Mind. Minnesota Studies in Philosophy of Science, 1, 253-329.

[12] Churchland PM. (1981). Eliminative Materialism and the Propositional Attitudes. Journal of Philosophy, 78, 67-90.

[13] Hardcastle VG. (1999). The Myth of Pain. Cambridge, Mass.: MIT Press.

[14] Roth M. (2012). Folk psychology as science. Synthese, 189(4), 1-12.

[15] Stich S. (1983). From Folk Psychology to Cognitive Science. Cambridge Mass.: MIT Press.

[16] Goubert L, Vlaeyen JW, Crombez G, & Craig KD. (2011). Learning about pain from others: an observational learning account. The Journal of Pain, 12(2), 167-174.

[17] Chalmers D. (1996). The Conscious Mind. Oxford: Oxford University Press.

[18] Searle JR. (1992). The Rediscovery of Mind. Cambridge, Mass.: MIT Press.

[19] Coghill RC, McHaffie JG, Yen YF. (2003). Neural correlates of interindividual differences in the subjective experience of pain. Proceedings of the National Academy of Science USA, 100, 8538-8542.

There is broad agreement among researchers that the minimal necessary neural pathways for pain are in the human fetus by 24 weeks gestation [1, for review]. However, some argue that the fetus can feel pain earlier than 24 weeks because pain can be enabled by subcortical brain structures [2,3,4,5]. Other researchers argue that the fetus cannot feel pain at any stage of gestation because the fetus is sustained in a state of unconsciousness [6]. Finally, others argue that the fetus cannot feel pain at any stage because the fetus lacks the conceptual postnatal development necessary for pain [7,8,9]. If a behavioral and neural reaction to a noxious stimulus is considered sufficient for pain then pain is possible from 24 weeks and probably much earlier. If a conceptual subjectivity is considered necessary for pain, however, then pain is not possible at any gestational age. According to [1], much of the disagreement concerning fetal pain rests on the understanding of key terms such as ‘wakefulness’, ‘conscious’ and ‘pain’.

A motivation for thinking conceptual subjectivity is necessary for pain is the idea that subjective experiences such as pain cannot be reduced to or identified with the objective features of the brain [7,8,9]. All pains are personal experiences and therefore entirely subjective; all brain states are physical events and therefore entirely objective. There is a fundamental divergence between pain and the brain. Thus, pain cannot be in the brain. The basic argument:

1. Pain experiences are subjective.

2. Brain events are objective.

Therefore, since pain experiences and brain events fundamentally diverge,

3. Pain experiences are not identical to brain events.

Is this a good argument? Let’s examine its first premise – ‘pain experiences are subjective.’ On a reasonable interpretation of its meaning, to state that ‘pain experiences are subjective’ is to state that pain experiences are knowable by introspection. However, since brain events are not knowable by introspection, pain experiences cannot be identical to brain events. Here is the argument:

1. Pain experiences are knowable to me by introspection.

2. Brain events are not knowable to me by introspection.

Therefore, since pain experiences and brain events fundamentally diverge,

3. My pain experiences are not identical to any of my brain events.

Once the argument is represented in this form, it is clear that it is fallacious. This can be clearly observed if we compare the argument with the following example:

1. Ibuprofen is known to me to relieve pain.

2. Iso-butyl-propanoic-phenolic acid is not known by me to relieve pain.

Therefore, since ibuprofen and iso-butyl-propanoic-phenolic acid fundamentally diverge,

3. Ibuprofen cannot be identical to iso-butyl-propanoic-phenolic acid.

The premises in the example are true, but the conclusion is known to be false. The argument is fallacious because the core idea of the argument – ‘fundamental divergence’ – makes an erroneous assumption; namely, it assumes that a thing must be known by somebody. But the property ‘being known by somebody’ is not a necessary feature of any thing, much less a property that might establish its identity or non-identity with some thing otherwise known. The truth of the premises may be due to nothing else but my ignorance of what turns out to be identical with what. These considerations challenge the assumed epistemology in the conceptual subjectivity view of pain.

They also challenge the related claim made by proponents of conceptual subjectivity that any description of a pain given in objective scientific terms will necessarily always exclude the personal experience of that pain [7,8,9]. The argument made here is by now familiar: since descriptions of pain in personal subjective terms are different from scientific descriptions of pain, it follows that a pain and its private subjectivity cannot be identical with a brain event and its public objectivity. Only persons can feel pain – brain cells and protein channels can’t. Clearly, the argument begs the issue in question: whether or not the subjective features of a pain I personally experience are identical with some objective features of my brain that might be discovered by neuroscience is precisely the question at issue [10,11].

Besides, in order to understand a scientific explanation of pain, neuroscience does not require of a person that he both understands the explanation and feels pain as a condition of understanding. Neuroscience aims to explain pain, that is its main purpose. Too much is demanded of neuroscience if, in addition to formulating an explanation of pain, it is meant to re-create pain in somebody as a requirement of understanding [10,11]. This expectation is therefore much too strong.

References

[1] Derbyshire SWG, Raja A. (2011). On the development of painful experience.Journal of Consciousness Studies18, 9–10.

[2] Anand KJ, Hickey PR. (1987). Pain and its effects in the human neonate and fetus. New England Journal of Medicine, 317(21), 1321–1329.

[3] Anand KJ. (2007). Consciousness, cortical function, and pain perception in nonverbal humans. Behavioral and Brain Sciences30(1), 82–83.

[4] Lowery CL, Hardman MP, Manning N, Clancy B, Whit Hall R, Anand KJS. (2007). Neurodevelopmental changes of fetal pain. In Seminars in perinatology, 31(5), 275–282.

[5] Merker B. (2007). Consciousness without a cerebral cortex, a challenge
for neuroscience and medicine. Target article with peer commentary and author’s response. Behavioral and Brain Sciences, 30, 63–134.

[6] Mellor DJ, Diesch TJ, Gunn AJ, Bennet L. (2005). The importance of ‘awareness’ for understanding fetal pain. Brain research reviews49(3), 455-471.

[7] Derbyshire SWG. (2012). Fetal analgesia: where are we now? Future Neurology7(4), 367-369.

[8] Derbyshire SWG. (2006). Controversy: Can fetuses feel pain? BMJ: British Medical Journal332(7546), 909.

[9] Szawarski Z. (1996). Do fetuses feel pain? Probably no pain in the absence of “self”. BMJ: British Medical Journal313(7060), 796–797. 

[10] Churchland PS. (2002). Brain-wise: V: Studies in Neurophilosophy. MIT press.

[11] van Rysewyk S. (2013). Pain is Mechanism. PhD Dissertation, University of Tasmania.

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