REDUCTIONISM
An intellect which at any given moment knew all the forces
that animate Nature and the mutual positions of the beings that comprise it,
if this intellect were vast enough to submit its data to analysis, could condense
into a single formula the movement of the greatest bodies of the universe and
that of the lightest atom: for such an intellect nothing could be uncertain;
and the future just like the past would be present before its eyes. Pierre Simon Laplace, Philosophical Essay on Probabilities (1814).
The highest object at
which the natural sciences are constrained to aim, but which they will never
reach, is the determination of the forces which are present in nature, and of
the state of matter at any given moment ‑ in one word, the reduction of all the
phenomena of nature to mechanics." Gustav Robert Kirchhoff, 1865.
The idea that all movement could in theory be
reduced to simple laws of nature was first recorded for posterity by Democritus
of Abdera in 4th Century BC Greece. This reductionist
outlook was also expressed by the Roman philosopher Lucretius during the 1st
Century BC. After the Dark Ages, when Greek and Roman ideas lost favor,
disillusionment with religion grew among thinkers and they became curious about
the ideas of those ancient challengers of piety and ritual. Isaac Newton wrote
about the forces of nature as a basis for understanding movement during the 17th
Century. The Philosophes of 18th
Century France restored rationalism as the ultimate guide to Truth. Scientific
discoveries continued to provide support to the reductionist notion, as shown
by leading 19th Century scientists such as Laplace and Kirchhoff.
During the early 20th Century the
reductionist paradigm came under challenge by Quantum Physics. The new physics
does not claim to require divine intervention or primitive spirits, but it does
appear to require randomness for events at physical scales the size of the atom
and smaller. The so-called Newtonian physics is correct as far as it goes, but
it cannot explain a category of physical events associated with the atom and
its interaction with light. At some future time it may be possible to portray
quantum physics with the same deterministic quality as Newtonian physics, but
for now it is prudent to assume that some events are subject to random outcomes.
The strict form of determinism called for by Newtonian physics should be
replaced by a probabilistic form of determinism. However, both forms of
determinism are reductionist since they are based on the notion that the
movements of all particles, and their interaction with light, conform to the
laws of physics. This last phrase is key, “conform to the laws of physics,” and
it is dealt with at greater length in Appendix A.
"Reductionism" either angers people or
delights them. The entire enterprise of science is based on reductionist tenets.
Whereas all scientists practice their profession in accordance with the
reductionist paradigm, there’s a part of the brain that is so opposed to it
that ~40% of scientists claim to not believe in reductionism. These conflicted
scientists are found mostly in the humanities, where muddled thinking is less
of a handicap; within the physical sciences there is almost universal belief in
reductionism (especially among the most esteemed scientists).
The end-point of reductionist thinking can be
most easily described by the following analogy: the universe is like a giant
billiard table, in which all movements are mechanical ‑ having been set in
motion by the explosive birth of the universe 13.7 billion years ago! Of course
this analogy neglects quantum physics, but nothing essential to our
understanding of the evolution of life, and of human nature, is lost by this
simplification. The march of events, from one moment to the next, is captured
by this simple-minded, deterministic view. Since this version of reductionism
is essential to the rest of this book, and since it is a fascinating subject in
its own right, I devote the rest of this chapter to a brief description of reductionism
and an appendix to its fuller treatment.
A Rigid
Universe
"The Universe Rigid" was possibly H.
G. Well's most important manuscript. It languished with the publisher, who
didn't understand it, and eventually it was lost. Instead of reconstructing it,
Wells turned its central idea into a story, The Time Machine (1895).
Two dozen years later, Albert Einstein published
his Special Theory of Relativity (1920), which expanded upon the idea, already
familiar to physicists of the day, of time as a fourth dimension. This concept
was treated in "The Universe Rigid" essay with unusual insight,
especially for a non-physicist. The following is a brief summary of it that
appeared in The Time Machine:
"... Suppose you knew fully the position and the
properties of every particle of matter... in the universe at any particular
moment of time:.. Well, that knowledge would involve the knowledge of the
condition of things at the previous moment, and at the moment before that, and
so on. If you knew and perceived the present perfectly, you would perceive
therein the whole of the past. ... Similarly, if you grasped the whole of the
present, ... you would see clearly all the future. To an omniscient observer ... he would see,
as it were, a Rigid Universe filling space and time ‑ a Universe in which
things were always the same. He would see one sole unchanging series of cause
and effect... If ‘past' meant anything, it would mean looking in a certain
direction; while ‘future' meant looking the opposite way. From the absolute point
of view the universe is a perfectly rigid unalterable apparatus, entirely
predestinate, entirely complete and finished... time is merely a dimension,
quite analogous to the three dimensions of space."
This passage describes the underlying principle
of what is referred to in today's parlance as "reductionism." It leaves no room for spirits, mysticism or
gods. Most intellectuals use the term "reductionist" as a disparaging
epithet, but I believe that reductionism is the crowning achievement of
human thought.
Mechanical Materialism
Reductionism is
the belief that complex phenomena can be "reduced" to simpler
physical processes, which themselves can in
theory be reduced to the simplest level of physical explanation where
elementary particles interact according to the laws of physics. The
ancient concept of Mechanical Materialism captures the essence of reductionism,
but relies upon the outdated concept that at the most basic level the particles
are like stones, and interact by hitting each other like billiard balls.
Nevertheless, reductionism is the fulfillment of
what Democritus and Lucretius dreamed about, a mechanistic world‑view that as a
bonus could also deliver people from the tyranny of religion. Lucretius would
agree with the statement: "There is no need for the aid of the gods, there
is not even room for their interference.... Man's actions are no exception to
the universal law, free‑will is but a delusion." (Bailey, 1926, describing
how Lucretius viewed the world).
It will be instructive to review mechanical
materialism before describing the version of reductionism required by modern
physics.
Imagine a game of billiards photographed from
above, and consider frames redisplayed in slow motion. After the cue sends one
ball into motion, the entirety of subsequent impacts and bounces are
determined. If this were not so, if the balls had a mind of their own, or if
some mysterious outside force intervened, then consistently good players would
not exist. Now imagine a very slow replay of the motions of the billiard balls;
millisecond by millisecond the movements unfold with an undeniable
inevitableness. A careful analysis would reveal that sustained momentum and
elastic collisions govern the placement and velocity of each ball in the next
millisecond.
Given two successive "frames," an observer
would know the positions and velocities of every ball, and he could calculate
their placement, velocities and future impacts for any arbitrarily short
instant later. He could thus predict the following frame, and the process that
allowed the prediction of frame 3 from frames 1 and 2 could be repeated for
frames 2 and 3 to predict frame 4. And so on, for all future frames. In this way, the observer could predict all
future movements (don’t worry about the fact that we've ignored friction).
By a similar process the observer could infer a
previous frame from any two neighboring frames. Thus, frames 1 and 2 could be
used to predict frame 0, etc. Therefore, by knowing any two frames, all future
and past frames could be inferred. This is the thought H. G. Wells captured
with his unpublished Universe Rigid
essay.
Reductionism
as a Basis for Physics
The 19th Century saw a de‑mystification of
various science disciplines. The reshaping was done by rationalists, building
upon the legacy of the 18th Century philosophes.
The rationalists firmly placed science on a footing that has endured throughout
the 20th Century. Like the machines of 19th Century inventors, the paradigm developed
by 19th Century scientists was "mechanistic."
Ernst Mach forced metaphysics out of physics (Holton,
1993, pg. 32). Chemistry was changed from a floundering quest for transmuting
common elements to gold, into a physics‑based understanding of atoms and
molecules. Darwin displaced God from the
creation of life by presenting his theory of evolution, even though this may
have saddened him personally.
By the end of the 19th Century, when Wells began
to write, the intellectual atmosphere was congenial to ideas that reduced
mysterious happenings to a juxtaposition of commonplace physical events. Each
event in isolation was conceptually simple. It is the mere combining of many
such events that cause things to appear incomprehensible.
Reductionism is based on a concept taught in
college Physics 101. I remember well that without fanfare the physics
instructor stated that there are only four forces in nature (gravity, electro‑magnetism,
the nuclear force and the weak force), and that these forces act upon a finite
number of particles that are pulled this way and that by the summation of all
forces acting upon each particle. In laboratory experiments where the number of
relevant forces can be controlled and can be confined to only 1 or 2, motions are
observed to be governed by a simple law: F
= m•a, or "force equals mass
times acceleration" ("acceleration" is the rate of change of
"velocity vector"). It is
easier to understand this law of nature by rewriting it in the form: a = F/m, which states that a particle's acceleration is proportional to
the sum of forces acting on it divided by the particle's mass. Mathematically, a and F are vectors, which is why these symbols are written in
"bold" typeface, and "m" is a scalar (no orientation is
involved); thus, the equation a = F/m keeps track of the 3‑dimensional
orientation of forces and accelerations. Since forces can originate from many
sources, they must be added together to yield one net force.
At every instant a particle is responding to
just one net force. It responds by accelerating in the direction of that force
(which has a magnitude and direction).
The particle's velocity vector changes due to its acceleration. Since the time history of a particle's
velocity specifies where it goes, the particle's "behavior" is
completely determined by the forces acting upon it. This description is called
Newtonian physics, and it reigned supreme throughout the 19th
Century.
Quantum Physics
During the late 19th Century a
disturbing number of laboratory measurements were made that defied explanation
using Newtonian physics. Radioactivity was a puzzle, for it seemed that atoms of
certain (radioactive) elements would spontaneously, and at random, emit a
particle. There was also the puzzle of atoms absorbing and emitting light at
only specific wavelengths, producing a unique spectral pattern for each atomic
element. Newtonian physics had no way to accommodate these and other puzzling
phenomena.
Quantum physics was
developed in response to these puzzling measurements, all of which were related
to mysterious phenomena inside the atom. The new physics expanded upon the idea
that everyday objects were constructed from electrons orbiting a nucleus
composed of protons and neutrons (now known to be constructed from 12
elementary building blocks of matter). It
was proposed that electrons could be thought of as a wave, with a wavelength
such that the only permitted orbital circumferences around a nucleus were those
with an integer number of wavelengths. Changes in an electron’s orbit involved
changes in energy, so if an electron moved to a higher energy orbit (farther
from the nucleus and larger in circumference) it must absorb energy from
somewhere (such as a photon of light) that had an energy corresponding exactly
to the difference in the electron’s energy in the two orbits – hence the
quantization of spectral absorption features for each atomic element.
As quantum physics
developed to explain more laboratory experiments related to the atom, the
theory became weirder and weirder. Quantum mechanics (QM) was developed to deal
with particles, and quantum field theory was developed to explain radiation and
its interaction with particles. Quantum physics has been described as inherently
probabilistic, or indeterminate, and has been characterized as having so much
"quantum weirdness" that our minds are intuitively unprepared to
comprehend it. Quantum physics “works” in the sense that it gives a better
account than any other theory for atomic scale physical phenomena. Contrary to
popular belief, it does not discredit Newtonian physics, which is still valid
for large scale phenomena; rather, it is more correct to say that quantum
physics supplements Newtonian physics. Almost
every physical situation can be easily identified as requiring one or the other
embodiment of physical law.
It now seems that
two of the aforementioned four forces can be "unified" (the weak
and the electromagnetic). One of the main goals of physics today is to create a
“unified” theory that incorporates all the explanatory power of the four forces
plus the weird but useful explanatory power of quantum physics.
One of the most
counter-intuitive properties of quantum physics is the notion that events are
not strictly determined but are only probable, and that particles are not tiny
things at a specific location but are probability functions in 3-dimensional
space. When a particle moves the probability function describing its location
moves. In the laboratory it is impossible to measure a particle’s position
without changing its velocity; and it is similarly impossible to measure a
particle’s velocity without changing its position. The Heisenberg Uncertainty
Principle quantifies the partitioning of position and velocity uncertainty.
Einstein believed,
but could not prove, that although we didn’t know of a way to measure a particle’s
position and velocity simultaneously with great accuracy, the particle
nevertheless has a well-defined position and velocity, and it interacts with
other particles as if this is so. His speculation was described as needing a
“basement level” of physical laws, which had not yet been discovered. With a
“basement level” of physical laws the apparent “unknowableness” of a particle’s
properties would be just that, apparent
“unknowableness.” The particle “knows” where it is located and how fast it is
going, and in what direction relative to the rest of the universe - even if
humans can’t know.
This “quantum
weirdness” is often cited to discredit the idea that events are “determined.”
But we cannot rule out the possibility that future physicists will discover a
basement level of physical law, and that this will restore Newtonian physics as
a complete theory for all size scales. The new Newtonian physics would have the
old Newtonian physics as a first approximation, valid for use with the vast
majority of physical phenomena dealt with on a daily basis.
Starting here I will present only brief
summaries of chapter sub-sections that have been moved to Appendix A for this
Second Edition of Genetic Enslavement.
Levels of
Physical Explanation
The matter of “levels
of physical explanation” must be dealt with for the reader who is not prepared
to accept the existence of a basement level of physical law.
In the physical
sciences it is common to treat a physical process at a “higher level” than
atoms interacting in accordance with the most basic level of physical law, a = F/m and quantum physics. Instead, other “laws” are constructed for
everyday settings, either derived from the basic level of laws or derived from
experiment and deemed compatible with the basic laws. One example should serve
to illustrate this.
Consider the
atmosphere, which consists of an immense number of molecules. Any thought
of using a = F/m applied at the level of molecules for the purpose of predicting
the weather would be silly because of its impracticality. There is no way to
know the position and velocity of all the molecules in the atmosphere at a
given time for establishing the "initial conditions" required for
subsequent calculation using a = F/m. The meteorologist employs a “higher
level of physical explanation” by inventing “laws” that govern such aggregate properties
as "atmospheric pressure," “temperature,” and "wind speed."
In each case the
invented property and rules for using it can be derived from a = F/m, so these handy properties and rule for usage are “emergent
properties” of the basic level of physical laws. Every atmospheric scientist
would acknowledge that whenever a meteorologist relies on a handy rule, such as
“wind speed is proportional to pressure gradient,” what is really occurring in
the atmosphere is the unfolding of an immense system of particles obeying a = F/m.
Just because
scientists find it useful to employ "emergent properties" does not
mean that the emergent properties exist; rather, they are no more than a useful
tool for dealing with a complex system. A "pressure gradient"
doesn't exist in nature; it exists only in the minds of humans. Model
idealizations of an atmosphere can be used to prove, using a = F/m, that the thing
called a "pressure gradient" is associated with wind. But these very
proofs belie the existence of the concept, for they "invent" the
concept of a pressure gradient for use in a model that then uses a = F/m. The handy meteorology rules, and their "emergent
property" tools, are fundamentally redundant to a = F/m.
The refinements of
modern physics do not detract from the central concept of materialism, which is
that everyday (large-scale) phenomena are the result of the mindless
interaction of a myriad of tiny particles in accordance with invariant laws of
physics. Reductionists acknowledge the importance of the many levels for
explaining complex phenomena, but they insist that all levels higher than the
basic level of physical explanation are fundamentally “unreal” and superfluous,
even though the higher level of explanation may be more “useful” than a lower
level of explanation.
Science embraces
what might be termed the "first law of reductionism," that whenever a
phenomenon can be explained by recourse to a more basic level of physical law,
the “higher level” explanation should only be used when it is drastically
simpler to use and unlikely to be misleading. Whenever a higher level of
explanation is used, there should be an acknowledgement that it is being used
for convenience only.
Living Systems
Reductionists view
living systems as subject to the same physical laws as non-living systems.
Therefore, the behavior of a living system is an emergent property of a complex
physical entity. A living thing is thus an automaton, or robot.
The thing we call "mind"
is an "emergent property" of an automaton’s brain. The brain consists
of electrons and protons, and these atomic particles obey the same physical
laws as inanimate electrons and protons.
Such things as
"thoughts, emotions and intentions" are mental constructions of the
brain that in everyday situations are more "useful" than the laws of
physics for the study of behavior. In spite of their usefulness, they are
not actually causing the movement of particles in the living organism, and they
don't exist at the most fundamental level of understanding. Even “free
will” must be shorn of its essential features, and recast as another "emergent"
product of real causes.
“Consciousness,” like
“free will,” is also an emergent property of automatons, just as the
"wind" is an emergent phenomenon of the atmosphere. I don’t
object to the use of “consciousness” for the same reason that I don’t object to
the use of “wind” when an atmospheric science problem is to be solved.
It has been argued that the physicist exhibits
"faith" in extending what is observably true in simple settings to
more complicated ones. This assertion of faith is true, but the faith follows
from the physicist's desire to invoke a minimum of assumptions for any
explanation.
Some
Practical Considerations Concerning Levels of Explanation
The brain evolved, like every other organ, to
enhance survival of the genes that encode for its assembly. It should be no
surprise, therefore, to find that it is an imperfect instrument for
comprehending reality. If it is more efficient to construct brain circuits for
dealing with the world using concepts such as spirits and prayer, rather than
reductionist physics, then the "forces of evolution" can be expected
to select genes that construct brain circuits that employ these pragmatic but
false concepts. Since no tasks pertaining to survival requires the a = F/m way of thinking, the brain will find this to be a difficult
concept. It is a triumph of physics to have discovered that a = F/m and quantum physics rule everything!
A naive person might believe that the primitive
person, viewing everything in terms of spirits, is thinking at a higher level
than the scientist. This would be a ludicrous belief. A primitive is a lazy and
unsophisticated thinker. He is totally oblivious to reductionist "levels
of thought." As I will describe later, he uses a brain part that is
incapable of thinking rationally: the right prefrontal cortex. Human
evolution's latest, and possibly most magnificent achievement, is the left prefrontal cortex, which evolution
uses to usurp functions from the right
prefrontal cortex when rational thought is more appropriate (i.e., feasible). Too often contemporary
intellectuals will unthinkingly succumb to the pull of primitive thought, as
when someone proudly proclaims that they are “into metaphysics" (an
oxymoron).
A fuller exposition of this topic cannot be
given without a background of material that will be presented in later
chapters. For now, I will merely state that mysticism is a natural way of thought
for primitive humans. It is "easier" for them to invoke a "wind
spirit" explanation than the reductionist ones, such as a = F/m, or higher level derivative physical concepts. They do this
without realizing how many ad hoc
assumptions they are creating, which in turn require explanations, and this matter
is never acknowledged (as with invoking God as an explanation, without
explaining "God"). Their thinking may seem acceptable from the
standpoint of a right prefrontal cortex (or "efficient" from the perspective
of the genes that merely want to create a brain that facilitates the gene's
"goal" of existing in the future), but it is terribly misguided from
the standpoint of the thinker endowed with a functioning left prefrontal
cortex, that demands rational explanations with a minimum of assumptions. This
unthinking proliferation of ad hoc
assumptions bothers the reductionist, but it doesn't bother the unsophisticated
primitive.
Reductionism
is for the Few
H. G. Wells must have understood the issues of this
chapter. The reductionist paradigm was an important part of intellectual
thought during the 19th Century, and Wells grasped it more surely than even
many scientists today. Scientists, engineers and inventors must have been held
in high esteem during the second half of the 19th Century, and the first half
of the 20th. The per capita number of significant discoveries and innovations,
as measured by Asimov's Chronology of Science and Discovery (Asimov, informally
distributed in the 1980s, formally published 1994) peaked at about the middle
of this period (actually, 1910 AD, as described in Chapter 15, and specifically
Fig. 15.12).
Late in the 19th Century, after Darwin’s evolution by natural
selection instead of divine guidance had time to register with intellectuals,
the idea of “humans as automatons” was part of the climate of opinion. Thomas
Huxley was intrigued by this idea, and Darwin humored him by signing
letters with a reference to it (Sagan and Druyan, 1992, pg. 70). Reductionism
requires that all living things be viewed as automatons, or robots created by
evolution. Yet none of today’s academics seem brave enough to defend this idea.
Ernst Mach (1893) deserves mention as an early
champion of the idea that all branches of science will eventually be viewed as
unified. He was a continuing inspiration for those who attempted to advance
this perspective (Holton, 1993) throughout the first half of the 20th
Century. His was one of the most important in a series of “flame-bearers” for
keeping alive an idea that came out of ancient Greece with the writings of
Democritus of Abdura (Sagan, 1980).
Reductionist ideas were at least understood by
literary people during the early 20th Century. In 1931 novelist
Theodore Dreiser, for example, wrote "I have pondered and even demanded of
cosmic energy to know Why. But now I am told by the physicist as well as the
biologist that there can be no Why but only a How, since to know How disposes
finally of any possible Why." (Dreiser, 1931).
Sadly, we cannot expect today's intellectuals to
have the same profound understanding of the nature of reality as was exhibited
a couple generations ago by such writers and social commentators as Wells and
Dreiser. The quality of thought over time, in a specific subject area, is not always
progressive. As with civilizations, there is a rise and fall in the sophistication
of world views. Indeed, as the 21st Century begins we are in the midst of a
renewed interest in returning to the comforts of primitive outlooks, as
described in the next chapter.
Return to Table of Contents
This site opened: July 30,
2006. Last
Update: July 30,
2006