Einstein's Enlightenment

  

Chapter 4: Explanation, Evidence, Truth and Power

Introduction

We often hear that the truth is unknowable or that what is true is a matter of opinion. As the possibility of knowing truth is often doubted we are tempted to settle for beliefs due to their psychological appeal. If reality is unknowable this would be a rational strategy. If reality is so ridiculously complex that all true aspects of it are beyond our understanding, we should not waste our time pursuing truth. If this is not the case and we do have the capacity to understand significant aspects of our true circumstances then we should value systems able to convince us of their truth.

 

As discussed in previous chapters we are knowledge machines from the ground up. I believe that our capacity to know significant truths is a closed question. All cells conduct the chemical symphony that creates energy from glucose. Some reasonable definitions of the word ‘to know’ support a usage such as: ‘A cell knows how to convert glucose to energy.’ A definition including this kind of knowing, dissociated from conscious processes, would also support usages: ‘A bird knows how to fly’ or ‘A monkey knows how to keep its balance.’ Daniel Dennet has argued that consciousness may only be a negotiation mechanism to arbitrate amongst the myriad unconscious knowledge mechanisms. The definition of knowledge we are developing here includes unconscious knowledge of the kind noted above. According to this definition the world is replete with instances of significant knowledge. We are in essence entities that know a method of surviving in the circumstance in which we find ourselves. This knowledge has been embellished, honed and passed down to us through each generation of living thing since the beginning of life. As Henry Plotkin argues in Darwin Machines, a work that has transformed evolutionary psychology, intellectual forms of knowledge are simply new adaptations evolved from earlier ones.

 

Man incorporates all types of knowledge produced by Universal Darwinism. Knowledge associated with complex chemistry, biology and culture are all components of human beings. No other known being incorporates this full range of knowledge.

 

In a sense the relentless production of knowledge by Universal Darwinism represents an attempt by the universe to come to know itself. Science is arguably the most highly evolved mechanism providing this self knowledge. The details of the working of science provide insight into its ability to discover truth and bestow power.

 

Science, truth and power

For our purposes we might define power as the ability to cause the occurrence of phenomena at will.  This definition implies both physical and mental components of power. The mental components are involved in ‘our ability to cause something to occur at will’. The part about ‘causation of phenomena‘   implies some physical components.

 

People have a predilection to understand power mostly from the mental perspective. We seem to have built in mechanisms for attributing human-like motivations to many aspects of nature and we yearn to relate to nature in this manner.[i] People often attempt to invoke power through purely mental means. We implore ghosts, witches, saints and all manners of spirits to intercede on our behalf. This has gone on for millennia despite having virtually zero measurable effect. Still it is our first impulse when attempting to invoke power.

 

Unfortunately matters of survival seldom depend on the purely mental. There has to be a physical component; for survival takes place in the physical would and those of us here today are descended from extremely long lineages of beings that were able to make the right choices about survival.

 

Perhaps a clear example is war. War is an arbiter of power in that it clears the field of obstacles to ones ability to expropriate the resources of an area. With these resources in hand one can cause lots of phenomena to occur. War is definitely about survival in the real world, it can be a grinding, real, physical event that produces a clear outcome. It can leave a group with clear possession of some real estate.

War can also arbitrate ideas and mental traditions; it can be a deciding event in the conflicts of cultures. Many cultures cease to exist following a conquest.

 

War also involves the mental: tactics, strategy and technology. These are mental constructs crucial to the outcome. Often the day goes to him who has these kinds of issues well thought out. Power is never wielded by the mental alone; trying to influence spirits won’t do it. Only when the mental is in tune with the physical does it produce power.

 

Technological abilities may not be included in many peoples catalogue of abilities required by successful generals. Usually we think of abilities such as tactics and strategy. This is probably only confusion in the use of the word ‘technology’. If we had used the word ‘weapons’ instead no one would quibble unless with the implication that weapons are a mental component. But weapons are highly dependent on the mental. Whether one learns their particular culture’s art of flaking arrow heads or developing smart bombs, weapons require understanding of the world; they are a type of technology.  

 

With science weapons arbitrating colossal power have been devised. These weapons deliver awesome power: the ability to cause intense phenomena at will. The energy of modern weapons produce extremely intense phenomena; they are extremely powerful.  What is the source of that power? How after hundreds of millennia of fruitlessly invoking spirits have we in the last few centuries stumbled, so ill prepared, onto this vast source of power. How did it happen?

 

Well it happened because we have unlocked a new means of putting the mental in tune with the physical; a means of discovering truth and unlocking power.

 

A brief example will help to clarify the relation amongst scientific explanation, truth and power. At the turn of the century the foremost physicist of the day, Ernst Rutherford, believed he had disproved the theory of Darwinian evolution. He reasoned that the sun, if it derived its energy from any plausible physical source, would have burned out long before the billions of years required by Darwin’s theory to produce complex life on earth. Therefore the sun and earth could not have been in existence for the great length of time required by Darwin’s theory.

 

A scientific explanation of nuclear energy was not yet developed. Some data had been collected by investigators such as the Curies but nothing resembling our current explanation was available. In 1905 , as part of relativity theory, explaining the weird fact that the speed of light is the same for all observers, Einstein derived the formula E=mc2 , which means that a little matter is equivalent to massive amounts of energy. By the early thirties, a lot of data concerning the behaviour of stars had been gathered. It was known that they were composed mostly of hydrogen, with older stars having a higher proportion of helium than younger stars. In 1939 Hans Bethe explained that stars were fuelled by nuclear fusion where four hydrogen atoms fuse to form one helium atom. Four hydrogen atoms have slightly more mass than one helium atom. In a star the excess mass is converted to energy exactly according to Einstein’s equation. Bethe’s theory explained all the scientific data collected concerning stars and nuclear reactions. Within twenty years, using this theory, the hydrogen bomb had been developed and tested. We could create a mini sun here on earth, at will.

 

Human history has probably developed thousands of explanations, many of them religious, for the sun’s existence and functioning. Only the one developed by science conforms to the evidence, only science successfully puts the mental in tune with the physical and unlocks the powers of the sun.

 

It is the knowledge developed by Science that contains the ancient truths. The phenomenon of suns, replicated in scientific knowledge, has been in the universe since there first were suns. We have only recently developed scientific constructs, mental constructs that are in tune with this physical phenomenon. Scientific is discovery not invention. No evidence has been found to support the possibility that Religious knowledge predates culture. Religious knowledge is invention not discovery.

 

Science evolves toward truth

The theory of memes claims that all cultural traits that are learned from others or are imitations of behaviours are created and modified by the processes of evolution. Most systems of knowledge, for example theology, can be said to evolve. Each theologian accepts a shared body of knowledge, which is reproduced in her mind with some variations (adaptations) from the consensus beliefs. These adaptations may prove to have survival value and be past on to other believers. Thus the body of theology evolves.

 

All systems of knowledge evolve as they follow the Darwinian algorithm. In this sense science is not special and shares the field with other systems of knowledge. But what gives direction to theology’s evolution? What are the criteria that lend its adaptations survival value?  A major criterion must simply be conformity to the believers’ (especially the more influential believers’) religious intuition or other types of subjective advantage. In the view of meme theory theological adaptations have survival value depending on how well they mesh with and how attractive they are to the individuals’ existing meme complexes.  Confirmation by objective evidence plays little role in the survival value of theological adaptations.

 

The difference between the evolution of science and religion lies in the criteria that defines fitness of adaptations and therefore determines what will survive and be past on. Science demands that its knowledge conform to the evidence. Religion does not. Faith, an integral part of many religious systems, can be defined as a commitment to believe regardless of the evidence.

 

Evidence is important because there are reasons to believe it is our best guide to what actually takes place in reality. Scientific evidence is evidence confirmed by the senses. Our senses provide ways of knowing honed to a high degree of accuracy by evolution over geologic time. Knowledge that cannot bear the scrutiny of the senses is rejected by science.

 

This process gives direction to the evolution of scientific knowledge. Scientific explanations evolve to more closely conform to data confirmed by the senses.  Over time they tend to agree to more decimal places. As science unlocks the secrets of the material world observed by the senses it becomes more powerful. In some sense it is inescapable that the tremendous power of science lends credence to its claim to be a ‘true’ system of knowledge.

 

Scientific theories are rational stories whose accuracy is verified by experiments.  Experiments produce phenomena in the real world that may lend credence to a theory.  A valid experiment must be verifiable or able to be reproduced by other researchers. Experimental phenomena that can be reproduced by other researchers may also be produced by technicians at will.  This explains the power of science; it’s ability to cause phenomena at will. Experimental evidence binds science to the ‘real world’ and is the source of its power.

 

The scientific explanation of the sun’s working evolved a great deal in forty years. It grew in tandem with a growing body of scientific evidence, evidence composed of experiments revealing data to the senses. At every step in its evolution the explanation was constrained to fit the available evidence.

 

It seems clear that the scientific explanation of the sun’s workings evolved closer to the truth. One group of philosophers, deconstructionists, deny this. They contend that science is only one amongst many cultural bodies of knowledge and has no special claim to the truth. Paraphrasing Dr. Johnson, Deconstructionists, along with anyone else, are vaporized in the presence of atomic blasts and are thus refuted. In some sense science is not just another body of knowledge but one that can claim to have unlocked truths and powers of the world unmatched by any other system of knowledge.

 

A nagging question remains. Why should we prefer an accurate or ‘true’ system of knowledge over one that is less so. Why should ‘true’ explanations have survival value? Perhaps this preference is not new but is built upon the survival value of accuracy in sensory perception evolved in our ancestors from the earliest times.  Daniel Dennet makes this point:

 

Getting it right, not making mistakes, has been of paramount importance to every living thing on this planet for more than three billion years, and so these organisms have evolved thousands of different ways of finding out about the world they live in, discriminating friends from foes, meals from mates, and ignoring the rest for the most part.[ii] 

 

Our bodies reward our conscious minds when we behave in ways the body approves of and the body punishes us when we don’t. We experience pleasure and pain as part of a feedback mechanism designed by evolution to keep us on the straight and narrow. It’s why sex isn’t a pain.

 

On the pleasure side, endorphins are released into the blood stream at appropriate times and stimulate the brain’s pleasure centres. We gain pleasure from many things, good food, sex, family and creativity. Einstein’s claim that the cosmic religious experience is at the root of all science provides a testament to the pleasurable mental state induced by creative science and goes some way towards explaining the motivation of those who create science as well as those who strive to understand and appreciate it. 

 

Science is built with tools developed by evolution.

Perhaps the most distinctive human biological characteristic is our huge brain. This large size comes at an extravagant cost. It poses increased risk during child birth and consumes up to 20% of the bodies energy production. Explaining why we have a brain of this size and cost is a challenge to evolutionary theory. What is its survival value? Explanations based on biological evolutions are only partially convincing, it is difficult to imagine our remote ancestors receiving a biological advantage large enough to provide the required enormous differential survival. 

 

A recent suggestion by Susan Blackmore, based on meme theory, is more convincing[iii]. She suggests that our large brains developed due to their ability to manipulate memes. Memes, a concept introduced by Richard Dawkins, are:

 

" tunes, ideas, catch-phrases, clothes fashions, ways of making pots or of building arches. Just as genes propagate themselves in the gene pool by leaping from body to body via sperms or eggs, so memes propagate themselves in the meme pool by leaping from brain to brain via a process which, in the broad sense, can be called imitation."[iv]

 

 Blackmore postulates that selective pressure for large brains increased due to greater biological survival of those individuals best able to learn and manipulate memes. She takes the concept further and identifies memes as a second replicator, genes being the first.  Evolution of memes, such as science, is not strongly tied to biological survival, but follows its own logic of fitness.

 

Whatever their exact origins, we have both a large brain developed by evolution and a mature systems of knowledge, also developed by evolutionary processes. 

 

Parts of the human brain are very similar to the brains of those species who are our closest relatives. In particular our sensory systems are very similar. Parts of our brains are new and largely unique to humans, the parts that handle higher intellectual functions and memes. The explanations of science are clearly stored and manipulated in these new areas of the brain as are all other systems of knowledge. The distinctive characteristic of science, as a system of knowledge, is that it also utilizes functions of the old brain. The construction of new variant scientific explanations is performed in the meme handling centres of the new brain. Judgements resulting in the differential survival of these variants are formed on the basis of sensory data supplied by the old brain. New variants live or die, are passed on or ignored, depending on evidence revealed to the senses of the old brain.

 

In terms of meme theory, the most accurate knowledge tools produced by both types of replicators are integrated into scientific methodology. Scientific explanations, or memes, are replicated with variations. The fitness of these memes are judged by evidence supplied by the most accurate knowledge tools of genetic replicators; the senses. This synergistic utilization of functions from both the old and new brains powers scientific evolutionary progress. This synergy allows scientific explanations to be demonstrated in the real world for all to see. Seeing is believing. Scientific truth is thus believable in a manner unchallenged by other system of knowledge. 

 

Sense perceptions, functions of the old brain, straddle the conscious/unconscious boundary. On the unconscious side resides knowledge such as that involved with vision translating photons and patterns of photons into neural signals meaningful to other parts of the brain. On the conscious side are mechanisms for providing these signals with context and for altering behaviour according to the content of the signals. Sense perceptions have been evolving for eons as a useful way of knowing. They have given power to those who possess them and are almost universal within the animal kingdom. Competitors lacking highly evolved senses are unable to compete in almost all circumstances.

 

Clues abound that sense perceptions provide us with very reliable knowledge as compared with the speculative nature of higher intellectual mechanisms. For example the Law rightly has a preference for an eye witness over someone who witnessed the event in their imagination. A fact may be defined as something having objective reality or having been confirmed by the senses.

 

Of course the senses can be fooled. A group of eye witnesses may disagree as to significant aspects of an event. The claim here is not that the senses are perfect, only that they are our best and most trusted guide to many aspects of reality.

 

Science has been described as a mechanism for developing explanations that best fit the scientific evidence (Deutsch 1997, page 64). Scientific evidence is largely produced by experiments designed to expose some aspect of reality to the inspection of the senses. Measurements are made, readings are taken, and information is received in the conscious mind from the senses. These data points constrain the artistic freedom of the explanations and ultimately pronounce judgement on them.

 

Pre-scientific Greek philosophy extolled the virtue of pure thought over sense impressions. Aristotle argued that men had more teeth then women. This was accepted as the truth by European experts for nearly a thousand years. Aristotle arrived at this and many other beliefs through a process of pure thought; it made sense to his imagination. Truth existed in the human mind, everyday reality was a poor imitation of the ideal world and not worthy of study. Not until a more scientific era did it seem appropriate to actually look in peoples’ mouths, count their teeth and decide that in fact men and women had the same number of teeth.  Movements for human equality may only flourish during scientific eras, when some weight is given to evidence.

 

Evolution has increased the senses’ accuracy over geologic time providing their bearers with a tool promoting success. Knowledge from the senses is available to our consciousness. Wouldn’t a system of knowledge be most powerful if instead of denying the power of the senses it leveraged this power? Science does.

 

Evolution of life forms on earth has been going on for nearly four billion years. An astounding variety of complex designs have evolved during this vast expanse of time. That this was accomplished by natural selection without a plan or a designer is a central tenet of evolution. Natural Selection is based on the differential survivability of inherited characteristics. Each generation inherits characteristics from their parents and in each generation there is some random variation in these characteristics. Some variations will bestow greater reproductive success on their bearers than will others. The individuals possessing these variations will propagate more offspring, offspring tending to have these parental characteristics as well as exhibiting some variations of their own. In this manner each generation tends to accumulate adaptations that bestow reproductive success.

 

There is no plan. What can persist does persist.  What cannot persist passes away. In a sense it is very wasteful to have a great variety of designs tried out in each generation only to have most of them discarded. Wouldn’t foresight give better odds for survival? It would and evolution produced it when it produced consciousness in animals.  Consciousness allows us to simulate actions or courses of behaviour in our imaginations and see how they play out. Would attacking that Sabre-Toothed Tiger really be a good idea? Many courses of action endangering survival do not need to be tried out, we can see they are bad ideas and try to think of something different. Of course foresight is good only if it is true to its name and is somewhat accurate. Imagining totally inaccurate outcomes would be useless. It is clear that our imagination is not totally accurate. Aristotle could deduce different dental configurations for men and women, we are quite often surprised by things turning out different then we foresaw. Fortunately our conscious simulations are much better than nothing. Often we foresee important events and are able to take steps to optimize our situation.

 

Science is interplay between our senses and higher intellectual faculties. The imagination explores variant explanations which must live or die according to their fitness. Their fitness is in turn determined by their ability to explain evidence gathered by the senses. Science, a higher intellectual system of knowledge, explains how things work in the ‘real’ world, the world as revealed to our senses.  In this manner its explanations conform to the evidence, have power in the ‘real’ world and are thus confirmed to be ‘true’.

 

Decision Theory: The Science of Science

Science is a process integrating rational explanation with empiricism. A scientific theory lives or dies on its ability to rationally explain empirical data. This may seem a bit fuzzy as surely we can construct theories of nearly infinite variation concerning some given subject matter none of which explicitly contradict the collected data. For instance all explanations that do not relate to the collected data cannot be ruled out by the data. How are we to decide amongst them on the basis of data?  Decision theory is a mathematical framework for measuring the quantitative fit between empirical data and the theories competing to explain the data.

 

A basic tenet of decision theory ties the validity of explanatory theories to their ability to rationally predict data:

 

A theory T is explanatory of empirical data D if, had I believed T before collecting the data, it would have been rational for me to expect D (or other data of which D is typical).[v]

 

Decision Theory provides the mathematical machinery for measuring the fit between a given theory and the data it attempts to explain.

 

Pierre-Simon Laplace, a great scientist of the 16th and 17th centuries, was an early developer of decision theory and used it most effectively to fill in the details of Newtonian celestial mechanics. Celestial mechanics is the study of the motion of bodies within the solar system and has as its main theoretical underpinnings Newton’s second law of motion: F=MA. This famous physical theory relates the mass and acceleration of a celestial body to the forces acting upon it. In the case of celestial mechanics the force is Newton’s theory of universal gravitation and the acceleration of the body is usually described by its orbital path. The mass is a constant and is a property of the specific body. Data collected to test Newton’s theory usually focus on measuring the position of a celestial body at successive times. The body’s acceleration is the deviation of the body’s motion from a constant speed in a straight line. The body’s path is then predicted as a calculation directly from Newton’s theory relating the acceleration of the body to its mass, the mass of all other relevant bodies in the solar system and the body’s distance from them. The two results are then compared and close agreement of the data with the theoretical prediction is taken as experimental support for the theory.

 

Unfortunately the masses and distances required to calculate the theoretical predictions are only known within a margin of uncertainty. Measurements of these quantities give a definite answer but successive measurements do not give exactly the same quantity; there is some uncertainty in the measured value. This uncertainty usually is well described by the Bell curve, where the values of most measurements are clustered around some central value while measurements deviating from that central value will be less common the further they deviate from it.

 

One method pursued by Laplace to minimize the uncertainty in the theoretical calculation was to try to nail down the masses of the major celestial bodies in the solar system: the sun, the planets and their main moons, and to reduce the uncertainty in these values as much as possible. One illustrative success he achieved was with the mass of Saturn. First Laplace developed a basic tenet of Decision Theory, now known as Bayes’ Theorem, which relates the probability of a theory being true given some new data to both the support it has from previously existing data and from the new experimental data under consideration. He then specified the existing data relating to the mass of Saturn, including the facts that Saturn has sufficient mass to keep it rings from flying off and that it has insufficient mass to perturb the orbits of the inner planets beyond what   is observed. The new data he introduced concerned a series of measurements on the mutual perturbations in the orbits of Saturn and Jupiter. 

 

Putting these results into Bayes’ Theorem he was able to quantify the level of support that the data rationally bestowed upon his theoretical prediction for the mass of Saturn. He calculated that the data shows there are less than a 1 in 11,000 chance that Saturn’s mass deviates from 0.000284738 solar masses by more than 1%. During the subsequent 150 years since this theoretical claim, the accuracy of  measuring apparatus including orbiting telescopes and atomic clocks have increased by orders of magnitude and yet the current best estimate of Saturn’s mass lies well within the narrow range of Laplace’s theoretical prediction.[vi]

 

Laplace was the most productive researcher in the history of celestial mechanics and we owe this productivity, in part, to his understanding of Decision Theory. Before investigating an area he would routinely use Decision Theory to calculate the extent to which the existing data supported accepted theory. Only when the data suggested problems with the theory would he throw himself into that area of research. By screening the fit between empirical data and existing theories he could identify those areas where his efforts could be productive in developing new theoretical understandings more explanatory of the data and/or new data that could decide between the theoretical alternatives.


 

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[i] Boyer, Pascal (2001). Religion Explained. Basic Books, New York

[ii] Dennet D. (1995). Darwin’s Dangerous Idea. Touchstone Publishing, New York

[iii] Blackmore S. (1999). The Meme Machine. Oxford University Press

[iv] Dawkins R. (1976).The Selfish Gene. Oxford University Press. P 192

[v] Wallace David. (2002). Quantum Probability and Decision Theory, Revisited. Available online:  http://arxiv.org/PS_cache/quant-ph/pdf/0211/0211104.pdf

[vi] Jaynes, E. T., 1986, `Bayesian Methods: General Background (174Kb),' in Maximum-Entropy and Bayesian Methods in Applied Statistics, J. H. Justice (ed.), Cambridge Univ. Press, Cambridge, Available online  http://bayes.wustl.edu/etj/articles/general.background.pdf