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How to Simulate Consciousness Using a Computer System

Chapter 2

The "Biology" of Digital Life-Forms

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2.1 Introduction

In the previous chapter, I described the philosophical framework for understanding the nature of consciousness. I explained that consciousness can only be understood in its complete context; it can only be understood in terms of how it fits into our knowledge of reality in general and biology in particular: That is, consciousness can only be understood as a basic axiom in metaphysics and a survival mechanism in biology, an attribute possessed by some kinds of life-forms.

With that context as a foundation, we need to look closer at exactly what this means to the theory of how biology explains consciousness in higher animals and human beings.

2.1.1 Philosophy, Biology, and Consciousness

The new method for acquiring objective knowledge identified by Ayn Rand, concept formation based on the comparison of perceptual measurements, that I introduced as part of a brief explanation of Objectivist epistemology will ultimately have an effect on all of the sciences; but for the topic of this book, its consequences for biology and computer science are the most relevant. Rand's method has consequences for our understanding of the causality of life, and it also makes it possible to connect natural language to percepts in order to objectively demonstrate the connections between words and the objects we observe in reality.

For this chapter, however, two consequences pertaining to the causality of life are especially important: One is the complex nature of causality as it applies to biology, and the other is the role of complex causality as it applies to the function of consciousness as a survival mechanism.

It is necessary to explain these two consequences before I can go on to explain how to simulate consciousness in a computer system: I must first provide you with a more detailed context for life-forms and how they operate in reality. Having that context is prerequisite to being able to write the computer code for the causal relationships required to create a virtual environment in which consciousness can be simulated.

But the how of simulating consciousness cannot be understood, without knowing what consciousness is in more detail, and how it operates in biology.

There are two erroneous ideas that are implicit in our culture (and probably in your subconscious), and they must be challenged if you are to ever grasp the context required to understand the ideas I am presenting. The two ideas are:

• That the only form of causality is mechanistic causality.

• The idea that consciousness can exist independently of a living, physical body.

Most people never consider that there may be more than one form of causal relationship; they intuitively accept the mechanistic concept of causality as billiard balls colliding as the only way causality can exist in nature.

But this view does not explain the biology of life very well. Life is not so simple, as most biologists know.

While life-forms ultimately depend on a form of mechanistic causality, that particular causal relationship is not sufficient to explain the existence or function of life-forms because it cannot explain goal-directed behavior. Just as you could not explain the operation of the word processing program I am using to write this book only by means of the electrical principles that enable my computer to operate, you cannot explain the operation of the behavior of life-forms by means of mechanistic causality alone. Other information is required.

The wide acceptance of the second idea, that consciousness can exist apart from a life-form, is due to the mysticism that pervades every culture in the world; most people accept the idea that consciousness can exist on its own apart from a biological body because that is what they were taught, and most people have never questioned what they were taught, but just accept great bodies of ideas whole, never chewing and digesting them. As I pointed out in the previous chapter, most people start their thinking with other peoples' ideas, not their own observations of and inferences from reality.

Such people are the implicit idealists I referred to in the previous chapter, who use intuition and the intrinsicist approach to form their concepts, most of them unknowingly. However, the idea of consciousness independent of a living body, is false. It is fallacy identified in Objectivist literature as the Primacy of Consciousness, a fallacy that is the result of using a defective means of concept formation.₁

Consciousness does not exist apart from life-forms; consciousness is a process performed by the living bodies of life-forms, a series of actions, some automatic and some volitional, by which life-forms interact with the objects around them. Consciousness is a property or attribute of life-forms, a survival mechanism, not an object that can exist on its own. Actions cannot exist apart from the objects performing them, and consciousness is an action of a life-form;₂ it is a process that a life-form performs by interacting with reality as part of its life processes.

So, in order to understand how consciousness works, you must first understand how life works from the point of view of causality; you must be able to distinguish the kind of causal relationships by which life operates from those by which inanimate objects operate. And, you must understand that consciousness is not itself a primary existent, but an action that is an attribute of one. You must understand that consciousness is caused by life-forms and life-forms alone.

2.2 Biological Life-forms

Nearly every culture in the world is built around some form of Idealism and Mysticism, usually a religion, though there are many other forms of it.

Western science rejects Mysticism and Idealism in favor of Subjectivism and Materialism, which attempt to explain all phenomenon, including life-forms and all their actions, in simple mechanistic models. Materialism includes the ideas that consciousness does not exist and that concepts are simply pragmatic, arbitrary symbols for classifying data, symbols that may or may not correspond to reality. Scientists rarely question the mechanistic formulation of causality when it is applied to life therefore, because given their subjective approach to forming concepts, to do so is neither practical nor necessary. The mechanistic, pragmatic approach seems to work just fine in experiments and scientific papers for most scientists when thinking professionally.

Most people (including many scientists in their personal lives) accept without question the premise that conscious life-forms are either supernatural or mechanical. Their acceptance of one or the other of these views is a consequence of their implicit philosophical premises of Idealism or Materialism.

The latter view means that life-forms are natural machines that work on the simple principle of "billiard ball" causality just like their man-made "cousins." The apparently opposing views of Idealism and Materialism are a false alternative, and they are the direct result of the non-objective ways the people who hold them form their concepts. They are a false alternative that results from forming concepts by using either idealistic, intrinsicist intuition or materialistic, pragmatic subjectivism, as opposed to the direct observation of reality, measurement comparison, and objective logical conclusions inferred from observation.

2.2.1 Self-Powered Objects

Non-living objects do not move unless acted upon by an outside force. Some objects, however, such as stars or solar systems or the evaporation/rainfall cycle or fire seem to have a "life of their own" because of the way certain chains of cause and effect enable them to operate continuously over extended periods of time.

Other objects such as certain chemical processes that involve DNA or RNA molecules are not only able to operate for extended periods, but are even capable of self-repair. That does not mean that they are alive, however; it simply means that these molecules are more complex causally than other molecules.

Both of these facts have been validated by direct observation and scientific experiment.

Life falls into a separate category altogether. According to Ayn Rand, life is "self-generated, self-sustaining action." In other words, life is more than mechanistic, "billiard ball" causality; it is teleological because it involves goals, actions taken to achieve them, and a means of self-regulation to govern the actions. To understand what that means in a non-mechanistic sense, you must first understand that there is more than one kind of cause and effect.

2.2.2 What is Unique about Life-forms?

What makes life processes unique is the form of causality by which they operate. Dr. Harry Binswanger explains how this form of causality works in his book entitled The Biological Basis of Teleological Concepts.

One of the facts explained in this book is that living matter is fundamentally different from non-living matter, a fact supported by the science of biology. Dr. Binswanger discusses Ayn Rand's definition of life as "self-generated self-sustaining action" and emphasizes the conditional nature of living matter. He also proves why this definition is true by showing how the concept of conditionality as applied to life-forms is connected to biology and observable facts.

For example, at one point Dr. Binswanger quotes biologist Walter Bock to emphasize the distinguishing features of life-forms:

"1. Living organisms take in materials and energy from their environment;

2. They use the appropriate materials and energy for self-maintenance, self-repair, and self-reproduction;

3. Once they have died, they cannot be reconstituted- failure is irreversible."

These three properties make life-forms significantly different from inanimate objects and are what Ayn Rand means by life as self-generated, self-sustaining action.₃ This is not a intuitive or subjective assertion, but a fact based on observation and inference; it is connected to reality; it is objective. To prove this fact to yourself, check each assertion in the following paragraphs with your own observations of reality and conceptual inferences as you read them.

Survival Requires Continuous Action

If living matter stops acting to gain what it needs to survive, it does not merely become inert like non-living matter, it literally decays, disintegrates and ceases to exist.

The constant need to act to sustain life in the face of alternatives is the basis for the concept of "value" according to Dr. Binswanger. Living things are goal-directed because they need values, and it is through goal-directed actions that values are attained.

Machines do not face the alternative of life or death and hence the concepts of value, goal-directedness, and self-generated action do not apply to them, except in the context of the human values machines help attain. This extends to machines in the current state of the art that are copies of living things which are embodiments of the human value of wanting a machine to act like an animal or a person. If machines that simulate life-forms are to be truly life-like therefore, they must be able to select their own "values" and act to attain them to whatever degree that is technically possible.

To illustrate this point, Dr. Binswanger quotes biologist Albert Lehninger as follows: "A living cell is inherently an unstable and improbable organization; it maintains the beautifully complex and specific orderliness of its fragile structure only by the constant use of energy. When the supply of energy is cut off, the complex structure of the cell tends to degrade to a random and disorganized state."₄

To further illustrate the difference between living and non-living matter, specifically with respect to self-generated action, Dr. Binswanger quotes an article called Living and Lifeless Machines by R.O. Kapp.

Of the source of energy for living matter, Kapp says: "Let us now turn our attention to the fuel. In a motor car this is petrol and it is stored in a tank. In the human body it is chiefly glycogen and is stored in the muscles, having been converted from glucose in the liver. The chemical processes during muscle activity include the combination of muscle protein with sodium. This protein is therefore another part of the fuel. So both the glycogen and the protein serve the double function of being fuel and being constituents of those muscle fibres that are at one moment moving parts and at another components of the frame. The living body is analogous to a motor car in which the chassis, brakes, cylinders, pistons, connecting rods, valves and bearings all contained combustible material, some of which was burnt whenever the driver put his foot on the accelerator."₅

The living cell is the basic unit of life; it is the dividing line between the living and non-living. The living cell depends on mechanistic causality in the form of physics and chemistry for its existence, but the cell itself is a more complex organization that requires more than physics and chemistry to explain how it functions.

All higher life-forms are composed of billions of specialized cells, each having evolved to perform some function to keep the organism, and hence the cells, alive and the chain of life unbroken.

In life-forms with automatic means of survival, it is the cells of a living organism that control its actions through the pleasure/pain mechanism, not the other way around. Such life-forms are not capable of self-destructive behavior. The goal of survival is built into their DNA.

But to say life is complex is not to explain how it works. In order to explain life, several new ideas are required.

2.2.3 The Concept of Emergent Properties

An emergent property is a property of an object that cannot necessarily be predicted from looking at its parts. In his book, Dr. Binswanger used the example of two hemispheres that will not roll separately, but will roll when glued together: "Rolling is thus an emergent form of action completely determined by the individual separate properties of the parts and their arrangement."₆

The concept of emergent properties is essential in explaining the complex processes that occur in life-forms, both real and artificial.

Life Requires Goal-directed Action

In his analysis, Dr. Binswanger shows that it is the conditional nature of life-forms that drives their behavior. Life-forms must act in order to survive; if they do not, they die, decay, and cease to exist. This means, in effect, that life-forms are inherently goal-directed. Their goal is continued survival, which their actions are intended to achieve.

In the context of their life as a whole, all actions that life-forms take can have one of two consequences: They can cause life-forms to survive or not. Actions that cause survival can be said to be of value to life-forms, to be the cause of their continued actions because they achieve the goal of survival; likewise, actions that cause the death of a life-form are not of value to it because they are self-destructive.

As Ayn Rand said: "Life is the standard of value."₇ The consequences of actions measured by this standard are always either values or disvalues.

This statement is validated by the observations and conclusions described in these paragraphs and the references to this book; they are its context, the links that explain what life is and why it is what it is. They explain how the concept of life is tied to reality. If you have been reducing the concepts you have been reading to your own percepts by following the links between their definitions and comparing them with your own observations, you will see why the statement is true. It is objective, a fact of reality.

Another way to put the point that life is the standard of value is that actions that lead to survival provide life-forms with values; all other actions, lead to death because they do not provide values. Some actions therefore, have value-significance because life-forms need them to survive. And, because they need values to survive, life-forms can be said to have gaining and keeping values as the goal of their actions; in other words, they are goal-directed.₈

It is the survival potential of objects and actions, therefore, that determines their value to a life-form. This fact is the very source and need of the concept "value" in the first place. If there were no life and death alternative, there would be no need to distinguish value from disvalue. Think of your own values. How much "value" would they have to you if you were dead?

The success of life-forms in achieving a value with any given action is not guaranteed. Their actions can fail. Failed actions do not cause survival, only successful ones do.

This situation leads to a complex, spiral form of causality identified by Dr. Binswanger that operates only for life-forms: They act to survive, and if they are successful, that action causes their survival, in which case they continue to exist to take further actions and the cause and effect chain continues; in other words, life-forms cause their own future existence by their successful actions to attain values; failure breaks the causal chain and death is the result. Whereas inanimate objects just exist, with no action required to maintain their existence.₉

These facts are the additional information mentioned earlier that is required to understand how life operates, and how life-forms are different from non-living objects. (I suggest you now take the time to think, to integrate these facts with your own experience, because they are absolutely prerequisite to understanding what follows.)

To distinguish the complex, spiral form of causality of a goal-directed agent's behavior from the cyclical behavior of inanimate objects, Dr. Binswanger has three tests. In order to be goal-directed, an agent's action must be:

• Self-generated (with some kind of fuel being an integral part of the agent's structure),

• Its goal must have a value significance (cause survival),

• And the action must be caused by the goal's value significance to the agent.₁₀

In other words, a goal-directed action must be an action a life-form originates using its own energy as opposed to something that just happens to it. The life-form must need the value that will result from the action for its survival, and the ultimate cause of the action must be the fact that the same action has caused the life-form' s survival in the past, thus enabling the life-form to stay alive to take another action in the present.

2.3 The Higher Animals and Man

In the higher animals and man, goal-directed behavior becomes even more complex, and two more layers of causality are needed to explain it.

2.3.1 Purposeful Action

Purposeful action is a still more complex form of goal-directed action. According to Dr. Binswanger, purposeful action is "a conscious action caused by the agent's desire for some anticipated consequence of his action."

In other words, purposeful action is an action of consciousness because the ability to feel a desire is a property of consciousness, and it presupposes a conscious life-form in order to exist. This means that there are two lower levels of causality required to explain purposeful action: The level of mechanistic causality by which the physics and chemistry of life operates and the level of goal-directed causality by which individual living cells and the various subsystems of life-forms operate.10

Consciousness and purposeful action as a property of complex cellular life-forms, is a more complex causal level that depends on these other two, and these ideas explain the more varied behavior of higher animals as opposed to that of simpler ones.

2.3.2 Necessitated vs. Neutral Actions

The only actions that are necessitated for life-forms are those required for their survival. The reason: Without survival, the life-forms cease to exist.

However, once a life-form has acquired a large enough supply of its essential values, it has in effect, bought itself some time when no actions may be required immediately for it to survive, or it may take any of several alternative actions with no significant effect on its survival status. Hence, it may be said that some actions of life-forms are neutral, neither values or disvalues to them, but always within some specific context.

For example, a squirrel that has stored a large supply of acorns may not feel driven by its instinct to search for food for a while and can engage in neutral actions, such as sleeping in its nest in some tree for a while or playing with another squirrel. Or, for a human who has enough money and is in good health, buying apples instead of oranges at the supermarket is a neutral action because it makes no difference to the person's survival status which type of fruit he eats this week.

Note - Strictly speaking, no action is completely neutral to survival; every action a life-form takes has some positive or negative effect on its life taken as a whole, is a value or a dis-value. However, within the context of narrower time scales and situations, some actions can be neutral to survival.

The point is that in higher life-forms at least, though all are caused, not all actions are necessitated. Some actions may be caused by factors completely internal to a life-form when selected from several alternative actions that are possible at a given time, none with consequences that will have any major effect on the life-form's survival.

This explanation of the behavior of life-forms is not possible using only simple, mechanistic causality.

2.3.3 Volitional Action

Volitional (free will) action is willful action by a conscious life-form; specifically, it is a capacity possessed only by human beings, the capability to choose certain actions from alternatives. Chosen actions are not necessitated actions.

All life-forms except human beings have automatic means of survival in the form of instincts or other means; in other words, they act automatically to survive.

Note - In this context, "automatically" means by instinct or other biological system, not a form of mechanistic automation.

Whether life-forms are scavenging for food, nest building, or reproducing, the intended outcomes are known in advance: They are gaining the values of food, shelter, and continued survival of the species. These values and the actions to attain them are programmed into the DNA of plants and animals. They have no choice but to follow that biological programming, though learning can modify it within a narrow range. This is true of all known life-forms, except humans.₁₁

Note - Experiments that supposedly show animals forming "concepts," using "symbols," and using "language" are irrelevant, and whatever they show, it is not thinking. The ability to associate some perceived objects with other perceived objects is a capacity shared by humans and many higher animals. Though the exact differences may not yet be clear between the associations animals make and human first level concepts, there is strong evidence they are not the same: Humans go on to form more and more abstract ideas; some of these abstractions are more general until an ultimate genera is reached (e.g. - chair, table, couch, lamp, furniture, household item, man-made object, object, entity); others are more specific (e.g. - animal, fish, trout, brook trout); still others are formed by complex combinations (e.g. - lamp, toaster, electricity, power company, hydro-electric project, dam, fish ladder, trout, reproduction, spawning); the choices are endless. Animals are not capable of forming these kinds of conceptual relationships or mastering human language to manipulate them. Researchers have spent thousands of hours and many years attempting to show how animals use human language, yet not a single conversation with one has ever been heard, nor has an animal originated theory ever been published.₁₂

According to Ayn Rand, volition is a property only Man possesses and it comes down to the choice to focus or not, which means to set thinking as a purpose or not. Man has the capacity to reason, but that capacity is not automatic; it must be activated by the choice to focus consciousness on some content and process it by putting forth mental effort.

Human beings do not choose actions or motives or ideas; these depend on previous conscious content or the method used to acquire that content and are not primary. Of all life-forms, only men have the capacity to form concepts and manipulate them to identify the world they perceive with their senses in symbolic form.₁₃

The ability to focus means to expend mental energy on some content to change it or connect it to some other content. Humans have the ability to do something animals apparently do not: Humans can manipulate the contents of their consciousness if they so choose, but they are not required to do so. The capacity is defined by human DNA, but using it is not automatic.₁₄

One of the ways humans can manipulate the content of their consciousness is to use one percept (such as a word or a variable) to symbolize or stand for one or more others. This ability is not free; it requires effort and energy; it requires the choice to focus conscious processes. It is not a necessitated action because it is accomplished using mental actions which are optional. (How such actions work will be explained in detail in Chapter 4.)

Indirectly, the ability to choose is caused by the previous actions a person took to cause his survival in the past; a person must first exist to choose or do anything in the present. But the actual choices made are not necessitated by previous conscious events. Like each step of a long journey, the choice to step forward must be made with renewed effort. In life-forms, only survival actions are necessitated.

In this sense, for humans some mental actions become first causes, when they are executed physically; some mental actions are not necessitated actions, but simply potential alternatives; they are optional, and they only cause changes in the outside world if an optional physical action is selected.

But the effort to take make choices and take certain actions does not have to be expended.₁₅

2.3.4 Volition and Concepts

The means of survival of human beings is not instinct, but reason, or in the words of Dr. Binswanger: "rational, purposefully directed cognition."

Reason requires concepts to function, and concepts are formed by a specific method of using one's consciousness. The method entails a process of selecting common properties of perceived objects or using other, pre-existing concepts as the data for defining a new concept, and this always occurs in a given context. The new concept is formed by a process of measurement omission; that is, the measurements of the properties of objects or other concepts are limited to specific ranges of values and used to form the definition of a new concept. The result (if this is done without error) is a complex hierarchy of knowledge about reality, knowledge that the automatic consciousness of other animals cannot form.₁₆

Volition is required because there is no way to perform this process automatically. Its results are not predictable.

Automatic processes are necessitated actions and depend on either knowing their intended outcome in advance or knowing a path to find that outcome by means of some implicit reference, such as with instincts in animals or electronic control theory (cybernetics) in machines.

Concepts and reason identify new knowledge for which neither the content nor how to find it is known. If the outcome or the path to new knowledge was known in advance, there would be no need to perform the process of producing it in the first place. Volition is one of the things that makes new knowledge possible because it is caused, but not necessitated action, and can it can therefore lead to the unpredictable.

Volition is yet another level of causal complexity that exists in one kind of conscious life-form: Man. Volition is a capacity that results from man's particular kind of consciousness, one that must make choices to form concepts to identify reality - so he can think - so he can act - so he can survive to cause his own future.

Volition presupposes the capacity for purposeful behavior which man shares with higher animals; this capacity in turn presupposes the capacity for goal-directed behavior, of life and its spiral causality of continuously attaining values; life itself presupposes the mechanistic causality that explains the dynamic nature of the rest of existence.

All of these levels are required to explain the behavior of human life-forms, and new properties emerge at each of them. All of the concepts in the explanation are linked by the objective method used to form them from observations of reality, and from the other concepts implied by their chain of definitions, an unbroken chain that forms the links between their contexts and connects all of them to reality.

Man-made Objects

One of the consequences of power of volition in human beings is man-made objects; these objects are not natural insofar as they would not exist in nature apart from man's choices. Their identity depends on human knowledge, which means it depends on human volition.

Natural objects are what they are as a result of whatever chain of mechanistic cause and effect happened to create whatever configuration of reality they happen to be. Moreover, they could not have been different from what they are. They are part of reality; natural objects are what they are, period.

Man-made objects, on the other hand, can be designed to fit any human purpose. So long as they are consistent with the laws of nature, it makes no difference (except to humans) what attributes they have. Human purpose is determined by human knowledge, and human knowledge is determined by thinking (or the lack of it); if a man thinks or not is determined by his own choice, and so are any man-made objects he may design.

Symbol systems are one type of man-made object.₁₇

2.4 Computer Simulations and Digital Life-forms

Life and consciousness, as natural objects, can only exist in nature the way they are found in nature - as properties of life-forms.

One highly flexible type of man-made object is the computer simulation program. It is flexible because it consists primarily of information; that is, computer based objects functioning not as physical objects, but as symbols or virtual placeholders for real objects, informational placeholders substituting for parts of reality. Symbol systems can be manipulated and reconfigured much easier than the objects they represent in reality, and without the risk or expense that can sometimes occur when real objects interact.

Simulations are performed routinely for inanimate objects in many fields of research and increasingly for life-forms in the relatively new field of Artificial Life (AL). In the current state of the art, most simulation programs simulate natural selection using genetic algorithms, ecologies of large groups of life-forms, and the automatic behaviors of life-forms navigating around various objects in their environment, gathering simulated food, and so on. Simple learning is also simulated.

Even though programs in the current state of the art simulate life to some extent, none that I have seen or read about is based explicitly on the multi-level kind of causality described in this book. Yet, to successfully simulate a higher life-form, that is precisely what is required.

A computer simulation of life and consciousness must mimic the essential causal nature of the higher life-forms if it is to have similar functionality.

2.4.1 Layered Models

A useful tool to understand systems with multiple levels is a layered model.

Computer systems are frequently explained in terms of such models. For example, the bottom layer of the model is the computer hardware, the next layer is the operating system, the third layer could be an application program, and a forth layer the functions an application program performs on a user's data.

Likewise, computer simulations of life-forms and consciousness can be explained using a layered model. As in the previous example, the computer hardware is the first layer and the operating system the second layer.

In the simulation system I will explain in detail in the next chapter, the third layer is a programming language development environment. In the case of the simulation system I have invented, in one implementation the third layer is the Prograph™ object oriented computer language from Pictorius, Inc., though that may be changed to the Java™ or some other environment such as C++ in the future.

The forth layer is the simulation program (the Digital Life-Form (DLF) Program), which is a prototype program I have written in Prograph. The DLF Program that simulates reality, digital life-forms (DLFs), and their interaction with it.

The design of the DLF Program also contains some additional layers that simulate the levels of complex causality by which life-forms operate, namely goal-directed behavior, perception of the simulated reality, purposeful behavior, volitional behavior, and concept formation.

2.4.2 Layered Models and Layer Substitution

One of the interesting aspects of layered models is the ability to substitute layers.

For example, some computer languages can run their programs on different hardware platforms unmodified. So if you think of a layered model with one of these programs as the fourth layer, it is possible to substitute different computer hardware (layer one), a different operating system (layer two), the appropriate version of the language environment for the new operating system (layer three), but still retain the same application program (layer four). For instance, the Java programming environment can run on computers that use any of the popular PC operating systems. You could, therefore, substitute any popular type of PC for layer one, substitute the corresponding operating system and Java environment software for layers two and three, and still run the same Java program in layer four.

This is, in essence, what DLF Simulation Technology does to simulate consciousness. The idea is to substitute mechanistic computer hardware and several layers of software for their mechanistic biological counterparts. Then simulate the complex causality of life-forms in the upper layers of the simulation system. The digital life-forms in the system will have their virtual teleological processes animated by the mechanistic causality of the computer simulation system in a manner that is analogous to the way in which biological life-forms are animated by the mechanistic causality of chemistry and physics.

2.4.3 Layered Models and Context Boundaries

Another important idea to grasp about layered models is that the layer boundaries are also context boundaries. This is important because operating principles can change across the boundaries from one context to another.

For example, in a computer system the hardware operates by various electrical principles that define the manner in which its components interact when an electrical current flows through them; across the context boundary in the second layer, the operating system functions based on mathematical and programming principles, as well as the requirements of a human interface; across the context boundaries in the third and fourth layers, a computer language development environment and an application program function according to logical process design, programing, and human interface principles; and in the fifth layer, the operation of a user's application program may function according to some other operating principle such as double-entry bookkeeping.

Just as with the example used by Dr. Binswanger of the property of being able to "roll" emerging from the fact that two hemispheres that have been glued together, new properties emerge from each layer in a layered model as you move from the context of one layer to that of another. In the top layer of the example I used in the previous paragraph, the property of being an accurate accounting tool emerges from the system as a whole when all the layers inter-operate together.

2.4.4 Complex Causality as an Emergent Property

In a similar manner, programs that simulate life-forms can have multiple layers; each layer simulates a causality level, and each is a separate context with its own set of operating principles and emergent properties.

If we assume the same lower layers I described for the DLF Program in Section 2.4.1, then the fifth level in the system can simulate goal-directed behavior, the sixth level can simulate purposeful behavior, and the seventh level can simulate volitional behavior and concept formation.

Just as the complex causality of real life-forms is dependent on the mechanistic causality of biochemistry, the complex causality simulated in layers five to seven in the DLF Program are dependent on the mechanistic causality of layer four and the ones below it in a computer simulation system.

The idea new to artificial life research being introduced here is the substitution of the form of mechanistic causality that supports the layers of complex biological causality; in other words, the substitution of a computer system for the mechanisms of biochemistry and a specially designed program to simulate goal-directed, purposeful, and volitional behavior as the interactions of a virtual entity with reality.

This may not seem like a new idea because people have been talking about simulating life with computer programs for years. To realize this idea is new, however, requires the recognition that biology is not mechanistic itself, which is a distinction not presently made by most computer scientists, and that an ordinary mechanistic computer program is therefore not sufficient to simulate life-forms.

The reason this important distinction is not made, as explained in the Introduction, is the epistemological approach most scientists use to form concepts and their implicit Idealism or Materialism. I hope that now the reader understands how using an objective method to form concepts differs from these other two approaches to knowledge, and can see how using an objective method leads to different conclusions about the nature of causality, life, and consciousness. These new and different conclusions, in turn, lead to very different strategies for simulating life and consciousness in a computer system.

2.4.5 Digital "Biology"

The key to understanding the "biology" of digital life-forms is realizing that they are not alive, but are calculations that are designed to mimic life. Furthermore, it is necessary to understand that goal-directed behavior is a more complex form of causality than mechanistic causality.

Once these concepts are reached, it is possible to design and a system which simulates the performance of goal-directed processes, and it is those new kinds of processes that then form the basis for simulating digital "biology" on a computer system.

2.5 Summary

In this chapter, I have set the biological context that is necessary to understand what is required to simulate consciousness in a computer system.

I have pointed out that while life depends on mechanistic causality, that level of causality alone is not sufficient to explain how life operates, and that goal-directed, purposeful, and volitional behaviors are the result of successively more complex forms of causality. Finally, I have related these levels of complexity to layered models and the concept of emergent properties, and explained how these ideas can be used as a basis for a computer simulation of the behaviors of life-forms including consciousness.

I have also explained why in order to understand the reasoning about this subject, an objective method of forming and validating concepts must be used.

Now that both the philosophical and biological contexts have been set, I can go on to describe how to implement their practical consequences in computer code that interacts with reality and reduce the simulation of consciousness to practice.