Quotation of the Week
"Two implicit tenets of Cognitive Science are Physicalism and the view of the brain as a biological computer (a universal Turing Machine).
Physicalism takes the mind to be causally inert; the computer model of the brain takes it to be multiply realizable.
Cognitive Science thus implies that neither the mind nor the brain matters: the first, because it can make no difference; the last, because it can be different."
Is This Generation Our Last?
Edited by Fiona Lundie and Scott Henney
The trajectory of climate change is incompatible with survival of the species.
The Industrial Revolution replaced muscle power with machines powered by the burning of fossil fuels, emitting carbon dioxide (C02) as a by-product. This technological advance exemplified the fact that the coupling of what can be and what ought to be done, is dysfunctional. In May 2013 the CO2 in the atmosphere reached, for the first time in 3 million years, the average level of 400 parts per million (ppm) by volume. 3 million years ago, during the Pliocene Epoch, that CO2 level caused a temperature increase that melted polar ice and increased sea levels by approximately 65 feet. About half of carbon dioxide in the atmosphere ends up in the oceans. CO2 acidifies the seawater, making the ocean inhospitable to life. Due to the recent and rapid industrialization of countries like China and India, CO2 levels in the atmosphere may reach 800 ppm by the end of this century. That level of atmospheric CO2 is incompatible with the survival of Homo sapiens as we know it. It is already too late to either reverse or stop the warming trend. Concerted, long term, international undertaking could delay by some 20-40 years the havoc that would be associated with the migration of hundred of millions persons from low laying areas. In human history, there was never any concerted, long-term international undertaking. The chance that such an undertaking would take place this time is virtually nil.
Humans are about to wrest from nature the future evolution of life on earth.
Some time during the first half of the current century humanity will be in a position to wrest from nature the future evolution of life on Earth. Such rapidly approaching development would be, without compare, the most significant event in the millions of years since humans branched from other primates. We just don’t know how to deal with this new state of affairs. Consider gene therapy. The crushing economic burden of health care cannot be alleviated by economic means. The current incremental improvement in the treatment of chronic diseases aggravates the economic burden. Gene therapy can prevent the expression of incurable chronic diseases. But there is a cultural divide between East and West on this issue. In Asia, pragmatic attitudes are likely to lead to the introduction of gene therapy, which would extend to the children of affected parents. This may begin to take place as early as next decade. In the West, it is a taboo to even to consider doing so. Left to itself, this new trend may result in genetic bifurcation of the current human population.
Averting extinction requires reconstruction of the foundations of knowledge.
Climate change and the prospect of controlling our future evolution shows that history is unidirectional: the past is not, and cannot possibly be, a guide for the future. Instead, commonalities of human nature provide the basis for charting a course between the perils and the promise of technology. Humans possess innate and universal sensory, emotional, and cognitive capacities, including the ability to evaluate actions and their consequences. Thus, human conduct, including ethical intuitions and concepts are a manifestation of human nature: they are universal to all human beings. This fact is a basis for addressing the future. However, this fact is denied by the currently dominant epistemology of Empiricism and Physicalism.
In fact, Physicalism has even removed ethics from the empirical domain. As a result, ethical and legal systems of the Western world, which have embraced Empiricism and Physicalism as their guiding conceptual frameworks, are relativistic: they are culture-specific, typically with a short time horizon. The factually false assumptions that underlie Empiricism and Physicalism are the primary reason for the non-universality of ethical and legal systems of the West. This non-universality precludes any concerted, long-term, international undertakings on global concerns, such as climate change or gene therapy. For these reasons, the first thing to be done is to review and revise the foundation of knowledge. This is a philosophical undertaking. It so came to pass that a focus on philosophy has emerged as a survival imperative.
Sensations are evoked in the brain - not imported into it.
This fact constitutes the new foundation of knowledge.
The most basic issue at the foundation of knowledge involves the distinction between what is, and what is not, physical. Your dentist can see your aching tooth, but not your toothache. The tooth is publicly observable while the toothache is private. By that criterion the tooth is physical while the private sensation of pain is not. More generally, the issue is the relation between the physical brain and the phenomenal experience elicited by it.
Sound as a physical quality is said to be a property of air vibration in the 20-20,000 Hz range that is recognized by the ears and then imported into the brain. However, sound can be elicited by direct brain stimulation, in the absence of air vibration and in the absence of input from the ears. This is the basis for the use of auditory prostheses for children who were born deaf due to dysfunction of the auditory nerve, as in the case of neurofibromatosis type II. The fact that sound can be elicited in the absence of air vibration or input from the ears constitutes a conclusive disconfirmation of the notion that sound is a physical property.
What is true of sound is true of all sensations. Vision, hearing, touch, taste, and smell are five of the sensory modalities of exteroception; each is represented in the cerebral cortex by a modality-specific area. The direct electrical stimulation of any modality-specific cortical area in a conscious person elicits a sensation of the corresponding modality: vision in the visual cortex, hearing in the auditory cortex, touch in the somatosensory cortex, taste in the gustatory cortex, and smell in the olfactory cortex. Thus, identical stimuli are sufficient to elicit qualitatively diverse sensations, as determined by the modality-specific cortical area stimulated. This fact demonstrates that such stimuli do not contribute to the qualitative nature of the evoked sensation. It proves that sensations are not imported into the brain, either from the senses or from the outside world through the senses. Consequently, sensations are subjective rather than physical properties. Furthermore, these findings show that our ordinary experience of the world is exclusively phenomenal. The physical is known by inference from the phenomenal. Put differently, what is deemed to be publicly observable (and thus physical) is ultimately based on observations from the perspective of first-person experience (and thus phenomenal).
Some 300 years ago John Locke (1690) postulated the notion that the brain of the newborn is like a blank slate (tabula rasa) until it receives postnatal input from the senses. David Hume (1748) then made explicit the implications of applying the tabula rasaassumption to cognition, thus forming the basis for his epistemology of Empiricism. Physicalism is the currently dominant epistemology. It was introduced early last century by a group known as the Vienna Circle. Physicalism may be characterized by three attributes: 1) it defines existence as physical, 2) consequently, it implies that if brain function produces as a by-product non-physical mental states then such states must be causally inert, and 3) it excludes teleological, or goal-oriented explanations in science because such explanations are not used in physics. One consequence of this position has been the removal of ethics from the empirical domain. Physicalism is based on a modified version of the tabula rasa assumption: in order to avoid the dualistic version of Locke, it deems sounds and colors to be physical properties of the external environment, rather then originating in the ears and eyes, respectively. Thus, the tabula rasa assumption is the most basic tenet that underlies present-day knowledge.
As noted above, the tabula rasa assumption has been proved false as to the notion that sensations are received from the senses. We now know also that that brains of newborn are not blank slates. The newborn has sensory, emotional, and cognitive mechanisms prior to any postnatal input from the senses. For example, the newborn likes sweet and dislikes bitter. The sensations of hunger and satiety are part of the mechanism that is involved in restoring glucose homeostasis and the sensation of hot and cold are a part of a mechanism that is involved in restoring temperature homeostasis. These sensations are innate in the sense of not being learned. And, except for pathological cases, these capacities are universal. Consequently, the most basic assumption that underlies present-day knowledge has been proved false.
It is now necessary to make explicit the epistemological consequences of replacing the tabula rasa assumption by its direct opposite. For example, the fact that no sensations are imported into the brain constitutes conclusive disconfirmation of Physicalism. A more fundamental consequence relates to physics. Imagining a sensation selectively activates the brain locus that evokes it. Imagining is mental while the consequent brain activation is physical. However, implicit in physics is the assumption that only physical causes can have physical effects. For this reason, brain activation by imagination requires that the foundation of physics be reviewed and revised.
Epistemology is a part of philosophy. It is therefore a task for the philosophic community. However, the philosophic community does not yet acknowledge the evidence that brains of newborns are not blank slates, and that sensations are not imported into the brain. Max Planck observed that paradigm change often involves generational transition. If Planck’s constant for paradigm change would apply here, then the most fundamental reconstruction in the foundation of knowledge in 300 years will remain a virtual terra incognita for some time to come. The possible consequences of the expected delay in undertaking the need for reconstruction of the foundation of knowledge may be best judged by the role of knowledge in evolution.
The capacity to obtain and use knowledge has emerged in evolution because it increases the range of conditions under which survival is possible. From the evolutionary perspective it is the action-consequences of knowledge that matter. Any such action couples what can be with what ought to be done. What can be done is represented by technology. What ought to be done is represented by a mixture of ethics, law, and public policy as reflected by national budgets. What can be done is the most successful part of human knowledge while what ought to be done is the most troubled. The industrial revolution, information technology, and biotechnology provide a background against which application of knowledge can be judged. The unintended and uncontrollable consequences of these technologies indicate that the reconstruction of knowledge is an urgent matter.
The industrial revolution. The industrial revolution introduced power production by burning fossil fuels, which emits carbon dioxide (CO2) as a by-product. From the last ice age to the industrial revolution, the average CO2 level in the atmosphere was about 280 parts per million (ppm) by volume. In May 2013 the CO2 reached for the first time the level of 400 ppm. That carbon dioxide level in the atmosphere existed during the geological epoch, the Pliocene, some 2.6 to 5.3 million years ago. Then, the 400 ppm CO2 level caused warming, which melted polar ice and caused sea level to rise to about 65 feet above the current level. Since the 1980’s, about half of the Arctic Ice cap melted. That ice cap is expected to be completely gone by midcentury. The current increase in CO2 level in the atmosphere increases by 4.5 ppm per year. At that rate it would reach 800 ppm by the end of the century. China, which is still in its early stage of industrialization, already replaced the United States as the largest polluter. It is too late to reverse or stop climate change. Climate change is the direct consequence of human actions and not a result of some natural phenomenon. These actions are manifestations of bad philosophy.
Innateness and the foundation of knowledge.
Darwin and the philosophic community. In The Descent of Man (1871), Darwin applied his theory of evolution to humans, concluding that we possess some forms of behavior that are innate. In the Expression of Emotion in Animals and Man (1872), he extended those conclusions to mental faculties. Earlier, John Locke, in An Essay Concerning Human Understanding (1705), proposed the contrary view that the brain of the newborn is like a blank slate (tabula rasa), and that postnatal experience is limited to input from the senses. The English speaking philosophic community has, by and large, accepted Darwin’s theory of evolution, but has thus far rejected Darwin’s application of evolution to the innateness of mental faculties. Present-day science has proved Darwin right.
Sensations are evoked in the brain. The use of auditory prostheses by those who are born deaf is the most common example demonstrating that sensations are evoked in the brain, and not imported into it. The electrical stimulation of the auditory nerve or auditory brain of children born deaf elicits sensations of sound (Kuchta J. 2004; Colletti V. et al. 2005). Hence, sensations of sound are evoked in the brain and are not received from the ears, and are not properties of air vibration. The same is true of all sensations (Sperry R. 1952; von Buddenbrock W. 1953/1958; Gardner E.P., Martin J. H. 2000; Brugger P. et al. 2000).
The scope the tabula rasa assumption. Locke’s tabula rasa doctrine underlies the following:
* Ethics and law
* The computer metaphor of the brain
Replacing the tabula rasa assumption. The replacement of the tabula rasa assumption by the fact that sensations and some other mental faculties are innate would constitute, by definition, the new foundation of knowledge. Nominally, the implications of such a change would be co-extensive with the implications of the tabula rasa assumption. Making explicit the implications of this paradigm change will inevitably become the central challenge confronting the philosophic community in the coming decades.
What ought to be done. The current technological revolution has given society a false sense of control over its future. But the opposite is true. The fact that present-day theories of knowledge, ethics, and law are based on a 300-year old misconception has deprived society the ability to effectively address these problems or even comprehend what these problems are. It is as if technology is catapulting humanity into an unknown future with a dysfunctional guidance system. The issue is survival, not philosophy. First, we must set aside the tabula rasa assumption, and then we must undertake the decades-long challenge of making explicit the implications of the new state of affairs.
Empiricism and innate cognition
Do we have innate knowledge about the world prior to experience? Empiricism is an epistemological position that denies that the newborn can have any knowledge about the world prior to postnatal experience. This position was developed by David Hume (1777/1975), who applied Locke’s tabula rasa assumption to cognition. Hume maintained that all knowledge is obtained only through the senses and denied that we may have any innate and universal cognitive knowledge about the world. Emanuel Kant (1787/1999) rejected that position, maintaining instead that we have innate and universal cognitive mechanisms, which impose structure on input from the senses. For example, Kant maintained that our perception of space as three-dimensional is innate and universal, and that it underlies Newtonian physics.
The perception of space as three-dimensional is innate. The retina provides two-dimensional visual information about perceived space. Yet, we perceive it as three-dimensional, even when looking with only one eye. This implies that the perception of depth does not originate in the eyes. It is not based on experience either: If a baby is placed on an opaque part of an otherwise transparent tabletop, it will look at the transparent part and will avoid crawling there (Gibson & Walk 1960). Taken together, these two observations – that depth perception does not originate in the eye, and that even a newborn baby perceives depth – show that there is an innate cognitive mechanism that imposes a three-dimensional interpretation on the input from the eyes.
Euclidean geometry and Newtonian physics. The so-called inverse square laws in physics follow from solid geometry of three-dimensions where lines of force are rectilinear (Figure 1). Hence, the inverse square laws are implicit in the knowledge about the world of the newborn, even prior to any postnatal experience. In this regard, Kant proved right.
Knowledge prior to experience. Present-day theories of physics are not yet in a final form, but they nevertheless constitute knowledge about the world. Newtonian physics is a familiar example: it is a non-final theory, but it constitutes knowledge about the world. There are aspects of Newtonian physics can be derived by taking space to be three-dimensional, and these constitute obtainable knowledge about the world prior to input from the senses – this is in direct opposition to the assumption that defines Empiricism, which may be defined as the denial that humans have, or can have, any knowledge about the world prior to input from the senses. So defined, Empiricism has proved to be factually false.
The inductive inference. Fundamental scientific advances involve the generalizing inductive inference. The inductive inference is not deductively valid. Like geometrical and mathematical concepts, the inductive inference is rooted in innate and universal cognitive mechanisms. Empirical investigation of these mechanisms is likely to shed light on the logic implicit in scientific induction.
Physicalism in the 20th century
Locke’s tabula rasa is dualistic. John Locke partitioned that which is perceived into primary and secondary qualities. He called primary qualities those qualities that are like size and shape, which he believed are attributes of the external world; he called secondary qualities attributes those that he believed to originate in the senses and not belong to external world, such as color and sound. This partition made Locke’s version of the tabula rasa assumption dualistic.
Rudolf Carnap. In the 1920’s, a group known as the Vienna circle, initially named after Ernst Mach, sought to purge the tabula rasa doctrine from Locke’s dualistic formulation. In his book The Analysis of Sensations (1904/1914), Mach stated that the first-person perspective underlies observations that are deemed public. Rudolf Carnap, who was a leader of the Vienna circle, reached similar conclusions in his book The Logical Construction of the World (1928/2003). Carnap therefore recommended that the first-person perspective be adopted as the basis for a non-dualistic reformulation of the tabula rasa assumption.
Otto Neurath. The first-person perspective is deemed subjective and, as such, as inconsistent with Materialism. Thus, Otto Neurath Neurath, an ardent (Marxist) Materialist, objected to the selection of the first-person perspective as the basis for a non-dualistic language of science. He insisted that the third-person perspective be selected instead. Carnap relented, and so it was. Carnap explained the reversal of his position by saying that the decision was not a necessary one, but a matter of choice. But soon thereafter, the notion that there is a choice in the matter was discarded. It is inexplicable why Carnap did not address this sharp departure from his stated position. Neurath then renamed Materialism as Physicalism.
Gilbert Ryle. In The Concept of Mind (1949), Ryle presented the reader with the choice between Physicalistic behaviorism and dualism. He then effectively argued against dualism and rested his case. The book implies that the rejection of dualism leaves Physicalism as the remaining alternative. This formulation relieved Ryle from the need of arguing against the first-person perspective, and even of the need to defend Physicalism. The book was a smashing success. It made Physicalism the quasi-official position of the English-speaking philosophic community.
Innateness of sensations and Physicalism. Empirical evidence demonstrates that sensations are innate and are evoked in the brain (Von Buddenbrock 1932/1963, Sperry 1952, Gardner & Martin 2000). As a consequence, sensory qualities are not publicly observable. It is therefore necessarily the case that observations that are deemed public are ultimately based on the first-person perspective: Physicalism is no longer tenable. It cannot be reconciled with the fact that the knowledge of the physical is derived from observation and inference, neither of which satisfies the criterion of physicality.
Interoception, needs and desires
Interoception. In humans, the sensations of hunger and thirst are innate and universal. They exemplify interoreception-based sensations, which are related to the maintenance of homeostatic internal body states (Cannon 1932/1963). The existence of universals of human nature underlies universals of human conduct. It provides the grounds for non-relativistic ethics and law.
Interoception and the tabula rasa doctrine. The tabula rasa doctrine implies that no needs and desires are innate. Only what is innate can be universal in human nature. Hence, the tabula rasa doctrine severs human conduct, ethics and law from human nature. It thus deprives ethics and law of any basis other than convention or dogma. The Vienna Circle recognized this implication of the tabula rasa doctrine when they removed ethics from the empirical domain. It so came to pass that other than convention or dogma, present-day ethics and law have no foundation.
Interoception and teleology. Interoception is involved in the homeostatic regulation of internal body states. Homeostasis is a teleological concept. Following Galileo, teleology was purged from scientific explanations until the last quarter of the 20th century. The mathematics of servomechanism restored the acceptability of teleological explanation ((Rosenbleuth, Wiener and Bieglow 1943). The cell, while it is alive, maintains some variables within narrow set-points that are far from thermodynamic equilibrium. The cellular mechanisms that make this balancing act possible are inherently homeostatic and are thus teleological in their function. Hence, teleology is a defining characteristic of life. Temperature homeostasis in mammals provides needed uniformity of chemical processes. This relative independence of variations of outside temperature is especially important for brain function.
Interoception, homeostasis and the mental. Mental states are evoked whenever voluntary action is needed to restore homeostasis (Figure 3). Such restoration is associated with positive affect. But shortly after restoration of homeostasis, the involvement of the mental is withdrawn, and operation returns to non-conscious regulation. Thus, in interoception, mental states appear when automatic mechanisms are insufficient to restore homeostasis, and disappear, soon after homeostasis is restored. Apparently, the mind plays a role in interoception.
An implication. The current application of the tabula rasa doctrine to needs and desires make it impossible to reach evidence-based consensus among people of different religions and ethnicities. Hence, the central moral imperative of our time is to set aside that doctrine, and then seek to derive human conduct from human nature. Such action would also provide an empirical foundation for the legal theory of natural law.
Neuroanatomic determinants of neural function
Two conflicting views of neural function. The discovery of the structure of DNA in 1953 showed the cell to be complex and autonomous. Prior to that discovery, the neuron was viewed as a tabula rasa cell, whose output is computable from its inputs alone. In fact, neurons emit input-independent output. For example, hypothalamic neurons that generate circadian rhythm do so also in the absence of any input and do so in vitro as well. The view of the simpleton cell led some to believe that the brain is a computer (McCulloch and Pitts 1943/1990, Smolensky 1994). In biology, function is structure-dependent, while in computers, it is not. Thus, if the brain is a computer, then there can be no unique neuro-anatomic correlates to any neural function or to a correlated mental state. This issue must be resolved in order that the neural correlates of consciousness (NCC) be identified. It is addressed below.
Structure-independent function. The general-purpose digital computer is an implementation of Alan Turing’s abstract, simple, and explicit formulation of computation, known as the Universal Turing Machine, or UTM (Turing 1936). The program, or algorithm, that represents a possible function of a UTM, can be processed on computers with different hardware designs. Thus, an algorithm does not, and cannot possibly have, a single unique hardware implementation.
Molecules, cells, and cell type distribution. Skin, muscle and bone cells of an organism differ in their constitutively-expressed proteins. This protein specificity accounts for both the cell’s phenotype and its intrinsic function (Figure 4). What is true of all cell types is true of brain cells. Their protein specificity determines both their phenotype and intrinsic function. Structural biology infers intrinsic function of a molecule from its structure. Molecular biology of the cell extends structure-dependence to the molecules constituting the cell. Cytoarchitecture maps the three-dimensional distribution of cell types. Korbinian Brodmann mapped the cytoarchitecture of the human cerebral cortex (1905/2006) into functional areas. For example, Brodmann area 4 is the primary motor cortex, area 17 is the primary visual cortex, and area 41 is the primary auditory cortex. This identification of intrinsic function is exclusively structure-dependent: it makes reference to neither interactivity nor connectivity.
Intrinsic neural function determines mental states. Structure determines intrinsic function and intrinsic function determines mental states. Hence, structure determinaes mental states.
The brain is not a UTM. This section constitutes the first empirical proof that the brain is not a Universal Turing Machine.
A glimpse of the new epistemological landscape. Present-day knowledge is still based on the empirically false assumption that sensations are imported into the brain. Making explicit the implications of the fact that sensations are evoked in the brain and not imported into it is a long-term process. The preliminary notes below touch on the following topics:
* Characterizing the physical
* The physical is an inference from the mental
* The mind affects brain and behavior
* Deriving human conduct from human nature
Characterizing the physical.
Concepts. The contrast between concepts and physical objects brings out the attributes that characterize physicality. A characteristic of existence is that it persists when observed by a person at different times (intrasubjective consistency), and by different observers (intersubjective consistency). By this criterion, mathematical concepts and operations are the epitome of objectivity. Hence, they satisfy the existence criterion. Concepts (e.g. triangularity), are apprehended introspectively, but are not publicly observable. Furthermore, the attribute of locatability in space is not applicable to concepts. In this sense concepts exist in the Platonic realm and thus ubiquitous.
Characterizing the physical. Consider, for example, a triangular equilateral tile in contrast to the concept of triangularity. The tile is physical, while the concept of triangularity is not. The tile satisfies the twin criteria of being located in space and being publicly observable; the concept of triangularity satisfies neither criteria.
Sensations. Red/green and yellow/blue are two sets of primary opponent colors. Looking at one such color (e.g. yellow) for a while produces an afterimage of the opponent color (blue, in this case). The blue afterimage is private, while the blueness of the sky seems publicly observable. However, the world of physics is colorless. In both cases the blue color is evoked by the visual cortex: sensations of color, like all sensations, are private. As such colors do not satisfy the criterion of physicality. The color afterimage is universal and intrasubjectively consistent. Thus, like concepts, color qualities satisfy the criterion of existence.
Perception of the physical. The physical is knowable by observation and inference. The observation involves vision, ouch and other sensory modalities of exteroception. The inference is mainly logical and mathematical and as such it is concept-based. Neither concepts nor sensation satisfy the criteria of physicality. If the non-physical is called mental then the physical is knowable as inference from the mental.
The mind matters – the causal efficacy of the mental. Imagining a sensation selectively activates he corresponding modality-specific cortical area (e.g. color the visual cortex, a tune – the auditory cortex). The act of imagining is mental, while the activated cortex is physical. Thus, the mind activation of the physical brain is commonplace. This fact points to a fundamental incompleteness of present-day physics.
Ethics and the foundation of the legal system. Two factors make possible the development of non-relativistic ethics, which in turn, provides foundations for the legal doctrine of natural law. The first factor is the existence of innate and universal needs and desires (e.g. hunger and thirst). It makes possible to derive human conduct from human nature. The second factor is the ability of the mind to affect brain and behavior. This fact provides the presently missing empirical grounds for holding persons responsible for their actions.
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