The Hard Problem of Qualia and Consciousness


H.1 The Essence of the Hard Problem of Qualia and Consciousness

H.2 Qualia and Consciousness in Animals

H.3 Qualia and Consciousness in Computers and Robots

H.4 Consciousness after Conception

H5. Remarks


The Hard Problem of Consciousness

The problems related to qualia and consciousness are ones of the most crucial puzzles of our lives, both from scientific and spiritual perspectives. They can be categorized into two major types. One type concerns the physical machinery necessary and sufficient for their occurrence and functions, while the other is about how and why they occur within a physical system. The former is called the easy problem because, at least theoretically, it is possible to find answers. The latter is known as the hard problem [1–19] because, even in theory, no scientific knowledge seemingly exists to provide a solution. Some individuals even believe that this problem is inherently unsolvable, a belief known as Mysterianism [4,12,19,20].

The way to find the answers to the easy problem is straightforward. Basically, it is a matching process: By scientific methods, pairing occurrences and functions of consciousness and qualia with certain neural circuits and processes. This can expectedly be done with current or near-future technology. However, although named the easy problem, practically, it is one of the hardest scientific endeavors of mankind. Yet, again, the answers are theoretically achievable. On the other hand, existing theories and knowledge seem unable to explain how phenomenal consciousness and qualia can occur from phenomenality-less (phenomenon-less) physical systems and why they should occur at all. Even though we finally know the exact neural circuits and processes for consciousness and qualia, there is no prospect that we can answer these problems. Essentially, it seems to be the problem of the current fundamental theory of physics being unable to explain how and why phenomenality can and should occur from the elementary particles and their interactions. Thus, the problem is hard.

Nevertheless, the real root of this conundrum is not the incompleteness of the fundamental physical theory but our lack of knowledge of the physical nature of qualia and consciousness. In the past, people did not know how and why lightning struck and had to resort to some mystical or divine concepts to explain it. But, once they knew it was an electrical phenomenon, the answers followed. Similarly, we cannot answer how and why qualia and consciousness occur if we do not know what they physically are. Theoretically, once we can ascertain what they are physically, we will understand their nature and can naturally answer problems about them, causing these puzzles to dissolve.

Based on the physical properties of qualia and consciousness and on current scientific evidence, this theory has resolved the problems of what qualia and consciousness are physically and ontologically, as carried out in Chapters 3 to 7, and the results are stated as Theorems IV and V. These theorems provide scientifically verifiable predictions. Up to the present time, they have not been invalidated by clinical or experimental findings and are thus sound. These sound, evidence-based theorems provide rational answers to the above and other related problems as follows:

H.1 The Essence of the Hard Problem of Qualia and Consciousness

H.1.1 What are qualia and consciousness?

Qualia: Physically and ontologically, qualia are neural signaling patterns (Theorem IV). Specifically, they are a special type of signaling pattern with information meaning qualia—mental phenomena that manifest what they are like, such as an image of a house, a sound of a song, and an odor of a flower—to the consciousness neural process. Signaling patterns of this special type are called Special Signaling Patterns (SSPs). Therefore, when some neural processes produce SSPs and the consciousness neural process reads them, it interprets them as qualia, and qualia naturally and inevitably appear in the consciousness neural process, and thus in the brain. This is how qualia occur in the physical brain.

Consciousness: Physically and ontologically, consciousness is the neural signaling state of the consciousness neural process (Theorem V). Specifically, it is a signaling state of a special type with information meaning consciousness to the consciousness neural process itself. A signaling state of this special type is a composite of signaling states with information meaning consciousness (awareness and experiences of what things are like, such as awareness and experiences of what an image of a house, a sound of a song, and an odor of a flower are like) to the consciousness neural process. These signaling states are called Special Signaling States (SSSs). Therefore, when the consciousness neural process produces a composite of SSSs and then reads it through reentrant signaling, it interprets it as consciousness, and consciousness naturally and inevitably appears in the consciousness neural process, and thus in the brain. This is how consciousness occurs in the physical brain.

Qualia and consciousness: It is essential to note that SSPs themselves are qualia and that SSSs themselves, consciousness. Because signaling patterns and signaling states are inherent in the neural processes, so are qualia and consciousness. Thus, no new entities emerge or are created from physical neural processes to be qualia and consciousness. It is only that some signaling patterns do not mean qualia (but mean something else), while SSPs do, and that some signaling states do not mean consciousness (but mean something else), whereas SSSs do. For example, when we are asleep, under generalized anesthesia, or in a coma, no neural processes produce SSPs or SSSs, and the signaling patterns and signaling states in these conditions mean something else, which is not qualia or consciousness; consequently, there are no qualia and consciousness in such conditions. However, when we wake up or recover from anesthesia or coma, qualia-producing neural processes change from producing signaling patterns that are not SSPs to producing those that are, and the consciousness neural process, from producing signaling states that are not SSSs to producing those that are. Accordingly, the meanings of the signaling patterns’ information change from not-qualia to qualia, and those of the signaling state’s information, from not-consciousness to consciousness. As a result, qualia and consciousness occur. Evidently, qualia and consciousness are not some new entities that emerge in the brain in these conditions but are simply changed signaling patterns and changed signaling states with changed information and changed meanings. The seemingly emergences of qualia and consciousness are actually changes of signaling patterns and signaling states, together with changes of their information and meanings.

Therefore, when there are no SSPs or SSSs, there are neither qualia nor consciousness. Thus, qualia and consciousness do not always exist. These facts have always been true since the beginning of the universe. In the distant past, in the primordial era of the universe when there was no life and in the early period of evolution when there was life but the nervous system had not evolved to exist yet, there were neither SSPs nor SSSs. Even at present, SSPs and SSSs do not exist in entities that are not animals with a nervous system. Furthermore, in animals with a nervous system, SSPs and SSSs do not occur in a variety of conditions and diseases, such as those exemplified in the above paragraph, and in the early fetal period when the nervous system has not developed yet. Therefore, there were no qualia and consciousness in the distant past, and there are neither in many entities at present.

Nevertheless, even though qualia and consciousness—or, equivalently, SSPs and SSSs—did not exist in the distant past and do not exist in many entities at present, patterns and information have always been present in physical entities. This is because, since the universe’s inception, all physical entities have always possessed patterns—specifically, patterns composed of their physical characteristics (Section I.4, Extra Chapter I: Information). For example, whether it is a living cell, an inert rock, or a molecule, each entity has a distinctive pattern formed from the physical attributes—spatial position, velocity, mass/energy, electrical charge, spin, etc.—of its constituents. This holds true even at the level of a single elementary particle, which also possesses a discernible pattern composed of its fundamental physical traits—spatial position, velocity, mass/energy, electrical charge, spin, etc. [21-24]. Further, because patterns are information (Section I.4, Extra Chapter I: Information), information always exists in all physical entities. Thus, both patterns and information are inherent in all physical entities. Again, this has been true since the birth of the universe.

The crucial point is evolution. Patterns and information, similar to everything else, evolve. Primitive physical patterns evolved into more complex physical patterns, then biological patterns, then neural patterns, and finally special kinds of neural patterns, the SSPs and SSSs, having information meaning qualia and consciousness, respectively, to the consciousness neural process, without any new entity emerging to be qualia and consciousness.

This explains the hard problem of how phenomenal qualia and consciousness emerge in physical systems. Really, qualia and consciousness are not novel entities and do not emerge from anything; they are evolved forms of the ever-present basic entities—patterns and information—which have always existed inherently in the physical systems since the beginning of everything.

H.1.2 How can patterns and information, which do not seem to have phenomenality, be phenomenal qualia and consciousness?

This problem is answered in the preceding chapter, The Explanatory Gap. Briefly, patterns and information that mean phenomenal qualia and consciousness do not display phenomenality when they are observed from the third-person point of view, which is the point of view we usually have when we think about them or examine them in laboratories. However, when they are read, not merely observed, from the first-person point of view, which is the natural point of view of the consciousness neural process, they naturally and inevitably appear as phenomenal qualia and consciousness to the consciousness neural process. The discrepancy in their manifestations occurs because, when they are observed from the third-person point of view, their information meanings are not interpreted and thus cannot and do not reveal themselves; by contrast, when read from the first-person point of view, their information meanings are interpreted and thus can and do reveal themselves.

H.1.3 Why do qualia and consciousness exist?

Qualia and consciousness exist in this universe because it is fundamental to the nature of this universe that they exist. And they exist in the nervous system—in the SSPs and SSSs—because, in this universe, it is fundamental to the nature of neural signaling patterns and signaling states that some of them are qualia and consciousness. To the consciousness neural process, some types of neural signaling patterns, the SSPs, mean mental phenomena that manifest what they are like or qualia, and some types of neural signaling states, the SSSs, mean awareness and experiences of what things are like or consciousness. This is a brute fact.

H.1.4 Why did qualia and consciousness occur, and why do they still occur?

At first, qualia and consciousness occurred because, at some evolutionary stage about 520 million years ago, it was possible for the nervous system, which was advanced enough then, to evolve new kinds of neural processes that were capable of producing SSPs, which were qualia, and SSSs, which were consciousness. Thus, qualia and consciousness occurred at some time in the past simply because the nervous system was advanced enough then and because, in evolution, variations always occur when possible.

At present, qualia and consciousness persist because there still are functioning neural processes that can produce them. Evidently, that these kinds of neural processes have endured since their inception signifies that they have been preserved in the evolutionary process. This, in turn, indicates that they and their products, qualia and consciousness, must yield some effects that help increase the survival chances of the species that possess them. Thus, qualia and consciousness still occur today because they must somehow help increase the survival chances of the species that possess them [32–47].

H.1.5 When do qualia and consciousness occur?

First, as discussed in H.1.4, qualia and consciousness began to occur in this world around 520 million years ago. After that, qualia and consciousness occurred whenever neural processes produced SSPs and SSSs. It is to be noted that it is impossible for qualia and consciousness to not occur when neural processes produce these signals because these signals themselves are qualia and consciousness.

H.1.6 How do qualia and consciousness occur?

Qualia and consciousness occur by the functioning of neural processes. Specifically, they occur by neural processes producing SSSs and SSPs, respectively. The SSPs themselves are qualia, and the SSSs themselves, consciousness—no additional entities emerge or are created to be qualia and consciousness.

H.1.7 How do we know that qualia and consciousness did not occur in some primitive animals before the time asserted in H.1.4, and is it possible that there are qualia and consciousness in some primitive or less advanced animals today?

Qualia and consciousness as we know them are defined as mental phenomena that manifest what they are like and awareness and experiences of what things are like, respectively. These complex phenomena require two complex neural structures: one for qualia and the other for consciousness. We have learned from various neuroscientific studies and experiments that such neural structures are exclusively located in the latest evolved parts of the brain—the neocortices of the brain (see neural correlates of consciousness in Section 6.6). When these cortical areas function, qualia and consciousness occur; when they change their functions, qualia and consciousness change their manifestations; when they stop functioning, qualia and consciousness disappear. Thus, qualia and consciousness as we know them never occur without functions of these areas. Therefore, qualia and consciousness as we know them must have occurred in this world only when these neural structures had evolved to exist and function in the brain, which was around the time estimated in H.1.4.

It is highly unlikely that qualia and consciousness as we know and define them existed in the past or do so at present in primitive animals that did or do not have advanced-enough neural structures to support occurrences and existence of the two phenomena. However, this question can be definitively answered only if we know the exact minimal neural structures that can create qualia and consciousness, which, to date, has not been the case.

H.1.8 Why can there not just be mental processes without qualia and consciousness?

There can be mental processes without qualia and consciousness, and this had been the case for a long time—hundreds of millions of years—from the moment the nervous system appeared on this planet to the time when evolving neural processes became advanced enough to be able to produce qualia and consciousness. When that time came, qualia and consciousness came into existence simply because it was possible. It is only since that time that mental processes with qualia and consciousness exist. However, it should be noted that, even nowadays, mental processes without qualia and consciousness still far exceed those with them in number—all the sub/non-conscious mental processes of the cerebral cortex and all the mental processes of the basal ganglia, thalamus, brainstem, cerebellum, and other parts of the nervous system are mental processes without qualia and consciousness.

H.1.9 Do qualia and consciousness have physical effects?

Qualia and consciousness have physical effects, as discussed in Sections 5.3 and 7.3. However, at present, we still do not know exactly what their effects are, but the overall effects must be beneficial because they have been preserved in the evolutionary process.

H.1.9a But why did the nervous system evolve qualia and consciousness to gain beneficial effects; could it not have evolved something else?

It could, and it has done so. In fact, before the nervous system evolved qualia and consciousness, it had been evolving and improving itself with other means since it appeared in primitive animals 700–650 million years ago [25–27]. From a pre-nervous system with scattered neuron-like cells (such as in sponges) to a primitive nerve net (such as in cnidarians), then a primitive nerve cord with primitive nerve ganglia (such as in flatworms), then a nervous system with a primitive brain (such as in mollusks), then a nervous system with a primitive cerebral cortex (such as in lampreys), and ultimately a nervous system with a more and more developed cerebral cortex (such as in reptiles, birds, mammals, and finally, humans) [25,29,48–59], the nervous system has been evolving to be more complex and more capable throughout time. Even after qualia and consciousness had evolved to exist by evolving new neural processes with SSPs and SSSs, other parts of the cerebral cortex that functioned without qualia and consciousness in their processes have not stopped evolving. They have been continuing to evolve to be more complex and more capable, resulting in higher intelligence, more language capacity, more manual abilities, etc. [50,52,60].* Even the cerebellum and other parts of the brain have proved to continue to co-evolve with the cerebral cortex [50,62] all the time, despite not having qualia and consciousness in any of their neural processes. Thus, the nervous system has always been evolving to be more complex and more capable, regardless of the absence or presence of qualia and consciousness.

(* These abilities do not need qualia and consciousness to function as evidenced by their unconscious function without qualia and consciousness in us—we know only the results of their functions, but we do neither consciously control nor even know how they function [10,61]. Also, they are anatomically and functionally separate from qualia and consciousness; evidently, they can be interfered with or destroyed without affecting qualia and consciousness.)

The creation of qualia and consciousness is just one possible path in the nervous system’s evolution. It remains to be seen whether creating qualia and consciousness is the end of this evolutionary path or whether neural processes with qualia or consciousness can evolve further into new kinds of neural processes with new kinds of mental phenomena that may be even more fascinating than qualia and consciousness. Also, it remains to be seen whether no-qualia and no-consciousness super-intelligences (i.e., super-intelligences without qualia and consciousness) rivaling or exceeding human intelligence (which has qualia and consciousness) can evolve into existence in some animals in the future. Indeed, this kind of development is already progressing rapidly in non-living entities: supercomputers without qualia and consciousness, which are now able to solve complex mathematical problems that humans can never finish in their lifetimes; they are also able to beat their own creators at complex, intelligent games, such as chess, Go, and bridges [63–67]. Someday, such supercomputers, which do not have qualia and consciousness (this point will be discussed in detail in Section H.3.1), may become the ultimate entities that are superior to their creators—humans, who have qualia and consciousness—in every way. Regarding animal intelligence without qualia and consciousness, if we consider the powerful capabilities of the cerebellum, which can process billions of signals and control millions of muscle fibers accurately in milliseconds without qualia and consciousness in their processes but can result in such marvelous motor feats as those performed by skillful gymnasts and master musicians, it is reasonable to speculate that some animals can possibly develop no-qualia and no-consciousness intelligence and capabilities. Even today, it is possible that some animals that demonstrate intelligence but have quite different brain structures from ours, such as octopuses and bees, may not have qualia and consciousness in their systems.

To enhance its functions, the nervous system has evolved many kinds of neural processes, signaling patterns, and signaling states. The generation of qualia and consciousness is not the necessary or the most effective path but merely one possible path for enhancing the nervous system functions.

H.1.9b Why does the nervous system not enhance all mental processes with qualia and consciousness; why does it enhance only some of them?

The cerebral cortex has evolved to be a broadly adaptable system that does not depend on fixed hard wiring of neural circuits alone but can also make use of information processing. However, this system requires an integration center that can coordinate information communications between several cortical modules, most importantly those that function for the final-stage perceptions of all external sensations and some internal sensations, cognitive perceptions (of space, time, self, non-self, etc.), other cognitive and executive functions (thinking, recalling past events, planning, deciding, language processing, etc.), emotion, and volitional motor control. Such systems can certainly operate without qualia and consciousness, as evidenced by the fact that computers and the cerebellum can also perform these kinds of functions very effectively without qualia and consciousness. However, as shown in Sections 5.3 and 7.3, qualia and consciousness have effects, and such effects can be beneficial. Thus, creating qualia and consciousness for all these important processes can yield critical advantages to the organism. It can enhance perception, cognition, emotion, memory functions, volitional motor functions, etc. [11,41,44,68–79]. It is probable that, because perceiving situations in the outside world correctly, analyzing them and forming responses to them effectively, and executing purposive responses appropriately, all to the greatest possible extent, are crucial to the being, it is beneficial and advantageous to enhance the mental processes that perform these important functions with the combined novel functions: qualia and consciousness. This is why qualia and consciousness evolved to occur in these mental processes. On the other hand, the lower mental processes, such as those in the basal ganglia, brain stem, and cerebellum, can perform their routine functions efficiently without qualia and consciousness. Qualia and consciousness in those mental processes are thus unnecessary and may even be disadvantageous because some resources would have to be diverted to create, operate, and maintain them. Therefore, the answer to this question is that enhancing some mental processes with qualia and consciousness is beneficial, but enhancing others is not.

H.2 Qualia and Consciousness in Animals

Do animals have qualia and consciousness?

Because similar neural processes have similar signaling patterns and similar signaling states, any animals that have neural processes similar to ours have signaling patterns and similar signaling states similar to ours. Consequently, because qualia are signaling patterns and consciousness is a signaling state, these animals should have qualia and consciousness similar to ours. Animals with brain structures, neural circuits, and neural processes fairly similar to ours, such as mammals (chimpanzees, elephants, dogs, dolphins, whales, etc.), are likely to have qualia and consciousness fairly similar to ours. Animals with brain structures, neural circuits, and neural processes less similar to ours, such as birds, reptiles, amphibians, and fish, are likely to have qualia and consciousness less similar to ours. Animals with brain structures, neural circuits, and neural processes very different from ours, such as arthropods (ants, bees, flies, etc.) or cephalopods (octopus, squid, nautilus, etc.), may have qualia and consciousness that are of different kinds from ours or may not have qualia and consciousness at all.** At present, this is still under debate, but theoretically, it could be answered with more certainty if the kinds of neural circuits, neural processes, signaling patterns, and signaling states for qualia and consciousness in humans and the corresponding ones in other animals could be identified and compared.

(** Although many kinds of animals, especially those in these three clades—vertebrates, arthropods, and cephalopod mollusks—exhibit complex cognitive functions [11,33,36,41,44,80] and although they have neural structures and dynamics that are functionally equivalent to ours (such as the visuotopic, tonotopic, and somatotopic maps in the cerebral cortices; the thalamus; thalamo-cortical loops; cortico-cortical loops; and reentrant signaling in these loops), which are the basis of consciousness’s existence and functions in humans [11,36,60,81,82], these findings are not definite evidence that consciousness exists in them. Although many authors argue for the possible existence of consciousness in some of such animals because of these findings [11,33–35,40, 41,44,80,81,83–90], others think that this issue is still unsettled [91–94]. Thus, it is still not unanimously accepted that some animals have consciousness.)

H.3 Qualia and Consciousness in Computers and Robots

H.3.1 Do computers and robots have qualia and consciousness?

As computers and robots have parts that function similarly to parts of the nervous systems of animals—sensors (camera, microphone, mouse/keyboard, radiation sensor, chemical sensor, etc.), central processors and controllers (computer motherboard, robot mainboard, etc.), and effectors (monitor, speaker, printer, broadcast antenna, robotic arms/legs, etc.)—and as they use electrical signals in processing and communicating information between these parts and thus have electrical signals representing various kinds of information circulating in their circuits, it is logical to speculate that qualia-like phenomena (similar to a red color image or a sound of note C, which manifests what it is like in our mind) may occur in their systems because some parts of their signaling might be qualia-like phenomena in the same way that some parts of human signaling, the SSPs, are qualia. At present, whether qualia-like phenomena occur in their signaling processes cannot be conclusively answered because we still do not know the specific characteristics of the signaling that can be qualia and qualia-like phenomena.

However, even if qualia-like phenomena do occur in computers and robots, they certainly do not have physical effects on any of the computers’ or robots’ circuits and functions because, evidently, all the circuits always function in the expected way that they are designed to do. It has never been found that circuits in computers or robots perform functions that have not been programmed beforehand or that their functions are affected by some unplanned, unknown phenomena such as the hypothetical qualia-like phenomena being discussed. Thus, even if qualia-like phenomena occur in computers or robots, they are unlike qualia occurring in us because they have no physical effects. Moreover, it is definite that present-day computers and robots, operating with present-day hardware and software, do not have consciousness and are not aware of and do not experience any qualia-like phenomena that may occur in them. This is because awareness and experiences of anything, including qualia-like phenomena, are additional functions and have additional information. Therefore, computers and robots would at least need specific, dedicated software and potentially also some specific, dedicated circuits to perform these new functions and manage the new information, specifically the information about awareness and experiences (of the hypothetical qualia-like phenomena) that is to occur in the processes. However, there are no such software and circuits in present-day computers and robots—all the software and circuits in present-day computers and robots are created to do some predetermined, specific tasks, such as word-processing or spreadsheet operations, picture- or video-editing/displaying operations, and the control of their peripheral devices (e.g., disc drive, monitor/printer, robotic arms/legs, etc.). None is developed to be aware of and experience qualia-like phenomena that may occur in their circuits, and none is designed to be aware of and experience what these phenomena are like,*** because at present, we, their creators, simply do not know how to construct such software and circuits. Therefore, it is absolute that present-day computers and robots, with their current circuits and software, do not and cannot have conscious awareness and conscious experiences of anything; that is, they do not and cannot have consciousness—awareness and experiences of what things are like. Similarly, this conclusion is true for all other present-day electronic devices and machines (mobile phones, automatic vending machines, automated industrial machines, etc.) and all current devices and machines that process information in other (non-electronic) ways (analog thermometers, analog barometers, analog odometers, etc.)—these present-day devices and machines, with their existing circuits or components and operating programs or routines, are not aware of and do not experience what things are like and thus do not and cannot have phenomenal consciousness. To repeat, this is simply because they do not have circuits or components and operating programs or routines that support conscious awareness and conscious experiences, or consciousness, functions.

(*** A similar concept was discussed before by De Sousa (2013) [95].)

At this point, some may argue that consciousness is a non-material phenomenon and thus may occur in the computer from something that is not the function of its electronic circuits, such as heat, moisture, chemicals, or some unknown non-material entity, or even from nothingness. However, if that is the case, then these kinds of consciousness will not have physical effects at all or will have just non-specific instead of specific effects, which are information-based, on the computer. This is because, even though non-specific effects on the computer’s system can result from things such as heat, moisture, or chemicals, which can cause glitches or more serious malfunctions in the computer’s system, specific effects, which must result from registering, processing, storing, retrieving, and utilizing information, occur only from information processing by specific electronic circuits in the computer system. Moreover, in the case of consciousness that supposedly occurs from some unknown non-material entity or nothingness, this kind of consciousness will not and cannot have any physical effects on the computer because the physical world is causally closed. Therefore, all these hypothetical kinds of consciousness cannot have specific effects on the computer system—such consciousness cannot result in computers or robots registering its occurrence in their systems, having awareness and experiences of what things are like, reporting its presence to others, storing its information in memory, processing its information for other activities, and so forth. Such hypothetical consciousness is thus different from our consciousness, which has specific effects and results in various physical activities, such as, in addition to the just mentioned activities, talking and writing about, having conferences on, and doing research and experiments on it.

In conclusion, although some non-material phenomenon may occur in computers or robots from something that is not part of the functions of the computers’ or robots’ electronic circuits and although some may call it consciousness, it cannot have specific effects on the computers or robots or cannot have physical effects at all; thus, it is not and cannot be the kind of consciousness that we mean when we think or talk about consciousness in people and that is defined in this theory.

H.3.2 How do we build computers or robots that have consciousness as we do?

To have consciousness as we do, computers and robots must be able to be aware of and experience what things are like. However, the ability to perform these two functions needs specifically arranged circuits with specifically designed software to create electronic processes with this ability.

Theoretically, to have consciousness in an electronic circuit, the electronic processes in the circuit must create a signal that has information that means awareness and experiences of what things are like to its relevant components. In detail, this means that some sub-circuits must create a signal that has specific physical effects on some other sub-circuits, causing them to have information meaning awareness and experiences of what things are like in them. This would make subsequent processes of these sub-circuits function with this information. For example, the sub-circuit that functions to report the state of the system will report that awareness and experiences of what things are like have occurred in the system, the one that functions to store information will be able to store that information in the system’s memory, and the ones that function to retrieve and utilize stored information will be able to retrieve the stored information to the system’s working processes and utilize it. However, the present major obstacle is that we do not know the characteristics of both the signal that means awareness and experiences of what things are like to the working circuit components and the circuit and process that can create such a signal.

(Please see related discussions about this matter in Section 8.1.2 What is the mechanism for a physical signal to mean a quale in Chapter 8 and in Section I.7 The mechanism for information to mean something in Extra Chapter I: Information.)

Another possibility is that, instead of trying to create the needed circuits, processes, and signals from nothing, we could try to imitate human qualia-producing neural circuits, consciousness neural circuits, their processes, SSPs, and SSSs. Although the exact characteristics of these components remain unclear, theoretically, there is nothing to indicate that it is not possible for us to discover them eventually. In theory, if we have this knowledge and if the possibility of creating such circuits, processes, signaling patterns, and signaling states is not restricted to carbon-based biological systems but extendable to silicon-based electronic ones, then computers and robots with phenomenal qualia and consciousness can be built by such imitations. This concept is in accordance with the principle of organizational invariance of Chalmers [3,4,96–98].

H.3.3 Can there be robots that behave identically to us but do not have qualia and consciousness?

No, there cannot. If robots do not have qualia and consciousness, they will lack information about these phenomena. Consequently, they will not be able to behave identically to us in the activities that depend on or are related to information about these phenomena. For example, they will not be able to think or talk about, have conferences on, write articles or reports about, conduct research and experiments on, and perform other activities regarding their qualia and consciousness, while we obviously can and do.

H.4 Consciousness after Conception

When does consciousness appear in a being?

Because consciousness is a composite of SSSs, it cannot appear when there are no SSSs. Accordingly, they do not appear at the moment of conception, the earliest formation of the nervous system, or the beginning of fetal brain development. It will begin to appear only when the consciousness neural process begins to function and produce a composite of SSSs. Obviously, consciousness cannot appear suddenly in the fetus but develops gradually as the consciousness neural circuit, its process, and the composite of SSSs that it produces mature little by little.

According to Stiles and Jernigan (2010) and Mashour and Alkire (2013), the developmental anlage of the thalamus, one of the necessary structures for consciousness, is present from around day 22 or 23 post-conception, and the thalamocortical connections, another necessary structure, are thought to be formed by week 26 of gestation [45,99]. Around the same time, week 25–29, electrical activity from the cerebral hemispheres shifts from an isolated to a more continuous pattern, with sleep-wake distinctions appreciable from week 30. Thus, both the structural and functional prerequisites for consciousness are in place around week 30 [45]. According to Zelazo (2007), the onset of minC (minimal consciousness) may be tied to a series of anatomical and behavioral changes that occur during the third trimester of prenatal development—between about week 24 and 30 of gestation [100]. Also, according to Lagercrantz and Changeux (2009), after week 24, thalamocortical axons grow into the somatosensory, auditory, visual, and frontal cortices, and the pathways mediating pain perception become functional around week 29–30 [101]. In addition, from Lagercrantz (2014), consciousness cannot emerge before 24 gestational weeks when the thalamocortical connections from the sense organs are established; thus, the limit of legal abortion at week 22–24 in many countries makes sense [102]. Therefore, it can be concluded from these findings that consciousness, at least in some rudimentary form, plausibly begins to appear in the fetus around week 24–30 of gestation.

H.5 Remarks

Until now, numerous scientists and philosophers have proposed various theories and concepts to address the hard problem; for example, please see References 6, 13, and 103–111. However, none seems to be accepted as the conclusive answer probably because none seems to satisfactorily answer how and why phenomenality can and should arise from the physical system. This theory offers a new approach. It first identifies, based on their physical properties, what qualia and consciousness are physically. Once they have been found to be informational entities in the form of neural signals, the hard problem dissolves. Signals and their information can mean anything, including something with phenomenality, such as qualia and consciousness. When some neural processes evolved to produce signals with these types of information, phenomenal qualia and consciousness naturally and inevitably began to appear in the nervous system, a physical system. And they should occur at some evolutionary stage because variations yielding new functions always occur when possible. Finally, they still exist at present likely because they can help increase the survival chance of the species that possess them. Thus, the hard problem can be solved with current scientific knowledge of signals, information, and evolution.

In the past, the sun seemed like God.
We could not answer how and why it occurred,
how and why it created its powerful light … and other puzzles
until we know what it is physically.

Consciousness is like the sun … and everything else.
We cannot answer how and why it occurs,
how and why it has phenomenality … and other puzzles
until we know what it is physically.

The hard problem of consciousness can be solved
by first solving the ontological problem.

> Go to The Explanatory Gap

< Go to Homepage “The Basic Theory of the Mind”

The Hard Problem: References

  1. Brogaard B, Electra Gatzia DE. What can neuroscience tell us about the hard problem of consciousness? Front Neurosci. 2016;10:395. doi: 10.3389/fnins.2016.00395.
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Keywords: The hard problem, The hard problem of qualia, The hard problem of consciousness