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How to think about a theory
of knowledge?
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I believe that what you now
have in your hands is a theory of knowledge. It starts with the most
fundamental idea; that knowledge is constructed of artifacts. People
construct and choose artifacts based on uniqueness. We pay special attention
to the important artifacts, assuring that they are generally unique; for we
believe that unique artifacts, both physical and conceptual, are precious.
Uniqueness gives us a flexible way of differentiating, handling, and
organizing the vast realms of experience that we face; a way to chose what we
must focus on and to construct artifacts and patterns of artifacts for
holding our experience.
There are only three different ways that an
artifact can be unique; by being different and thus distinct from other
artifacts, by being the same across other artifacts, or by matching and
mating other artifacts. These three forms of uniqueness define the three
fundamental tools and, therefore, the three elements of thought and
knowledge. We produce entities - our names and definitions - by
differentiating. We fashion sites - our categories and classes, our
concepts and generalizations - by collecting entities based on their
sameness. And finally, we make fasteners - our theories and
explanations - to link different sites by matching.
We constructed this theory and then
connected these unique artifacts to the Pattern of Knowledge to see
whether these abstractions, which we derived from uniqueness, fit our legacy
of intellectual history by explaining its periods, phases, and sequence. The
fit seems exact and strongly suggests that all of the knowledge we create is
explained by this theory. This is what a theory of knowledge looks like: a
simple, purely logical argument which provides a template for constructing a
pattern that then holds and connects experience in epistemology, intellectual
history, natural language, and mathematics.
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A Theory in Physics:
Electricity and Magnetism
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A short stroll into a very
special part of physics
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Since a theory of knowledge
is unfamiliar, it may be instructive to look at what a great theory in the
discipline of physics is like; and Maxwell's theory of the Electromagnetic
Field is the most beautiful example I know. Forgive me for again choosing an
example in physics, but this discipline does give us our purest and most well
thought out theories. James Clerk Maxwell, by 1860, had already established
his reputation as a first-rate physicist working on a wide variety of
problems when he turned his attention to the work of Faraday and the
difficulties in electricity and magnetism. It was this work that marked him
as the greatest physicist of the 19th century, and while he is less well
known, he is on a par with Newton and Einstein. Unlike mechanics - the study
of the motions of ordinary objects - which was well understood and elegantly
theorized by Newton and his followers, electromagnetism was then in a chaotic
state.
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First a little background
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There were a variety of
different and often complicated laws dealing with electricity and magnetism,
which generally melted down to three key ones. The electric force between two
static (not moving) charges was the easy one - Auguste Coulomb defined it in
1775, exactly mimicking Newton's Law of Universal Gravitation.
Coulomb replaced the masses (m) by
the charges (q) and the constant of Gravitation (G) by a
constant for electricity (k). The force of electricity, like the force
of gravity, varied as the square of the distance, indicating that it spread
out in straight lines. Coulomb carefully constructed an electric balance to
assure that this law fit the experimental data. Other than being either
attractive or repulsive, this force was very Newtonian.
Magnetic forces proved to be much more
complicated. Magnets always come with two poles locked together. The force
between magnets does not spread out in straight lines. And to make matters
worse, by Maxwell's time, the magnetic force was known to be produced by
electricity. What was clear was that a new force, the magnetic force, was
generated when an electric object moved - a very un-Newtonian notion. Andre
Marie Ampere, in 1818, formulated a law describing the force between two
parallel wires carrying electricity.
It was a mutation of Newtonian laws; the
force varied as the distance (d) between the wires and not the square
of the distance. And while the force was proportional to the currents (I)
in both wires, it was also a function of the length of the wire (l).
Things were getting messy.
Michael Faraday, a wonderful teacher,
perhaps the greatest experimentalist of the 19th century, and the inventor of
the dynamo, which produces nearly all of our electricity, found that moving a
magnet produced an electric current. His Law of Induction was still generally
Newtonian because it was still based on forces between objects, but these
forces no longer followed lines that were straight (witness iron filings over
a magnet) and Newtonian forces were straight lines. He called these curves
"lines of force," and their whole, the "magnetic flux."
If it flowed through a loop of wire and it produced a current in that loop.
Faraday's Law of Induction related the electric force (EMF) that produced a
current in a wire to the rate of change of this flux.
More than 75 years of attempts by world
class physicists had produced these and other laws of electricity and
magnetism under the Newtonian umbrella. Each was descriptive, based on a
familiar pattern and not on a fundamental element. Each was very different
and generally unrelated to the others in its form, in the way it looked, and
in the way it worked. The result was complex and ugly.
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The Electromagnetic Field
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Maxwell opened his great
paper "A Dynamical Theory of the Electromagnetic Field" published
in the fall of 1864:
The
mechanical difficulties, however, which are involved in the assumption of
particles acting at a distance with forces which depend on their velocities
are such as to prevent me from considering this theory as an ultimate one...
I
have therefore preferred to seek an explanation of the fact in another
direction, by supposing them to be produced by actions which go on in the
surrounding medium as well as in the excited bodies, and endeavouring to
explain the action between distant bodies without assuming the existence of
forces capable of acting directly at sensible distances.
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Even without a background in
mathematics or physics you will be able to appreciate the beauty and the
simple of this work.
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His theory, today written
in the simplified notation of vector Calculus with just four equations, is so
elegant and esteemed that we decal it on sweatshirts for college students and
babies. While the symbols used may appear foreign, the fundamental ideas can
be appreciated by all of us, just as we can feel the wonder of Beethoven's
9th Symphony even if we can't read a note or play an instrument.
The
theory I propose may therefore be called a theory of the Electromagnetic
Field, because it has to do with the space in the neighbourhood of the
electric or magnetic bodies, and it may be called a Dynamical Theory,
because it assumes that in that space there is matter in motion, by which the
observed electromagnetic phenomena are produced.
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A field is an environment. We
can describe it with vectors.
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The electromagnetic field
is an environment - a continuum - spreading out in space. It is a
"substance." Maxwell believed that this "ethereal medium"
was real. While there are a variety of ways to imagine such an invisible
medium that acts on only electric and magnetic objects, if you think of this
environment as an atmosphere with winds which blow only electric and magnetic
particles, then you will have a good metaphor. This wind, this field, has a
strength and a direction at every place in this continuum. It can be measured
by placing an electric or magnetic body at a point and plotting its direction
and its magnitude. We can imagine filling the field with electric wind-vanes
and magnetic compass needles, each pointing in the direction of the field and
varying in length to show the field's strength. Such arrows are vectors,
mathematical representations for both the magnitude and direction of the
fields.
In a simple case, a single charged particle
produces an electric field radiating spherically out from it, the electric
field vectors all pointing straight from the center like a pin cushion. This
field produces a force on a charged particle along that radiating vector.
Even in this static case, the field proved a powerful idea allowing Maxwell
to no longer think of forces "acting at a distance" between the
charges, but instead, of forces as the result of a field generated by a
charge acting on another charge. Forces no longer needed to reach across
space at infinite speed. But it was in the dynamical situations with forces
being produced by motions that the power of this idea became apparent. The
motions of electric charges produce a magnetic field and the motions of
magnets produce electric fields.
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The Calculus is the
mathematics of change, describing how fast something changes or how much
change has occurred.
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The search for explanation
and not just for description drives physics. The explanation of change is the
heart of the matter. Whether it be motion or fields, the uniform is the
starting point, the natural condition. The changing field, like the changing
motion is where the action is. We explain it by connecting a cause to the
rate at which the change occurs. For Newton force was connected to
accelerations, for Maxwell, the cause was connected to a changing field. The
rate of change is the realm of the Calculus, invented by Newton and Leibniz,
and initially developed in one dimension along the path of the motion. But
the field is three-dimensional and fortunately by the 19th century the
Calculus was extended to rates of change in three dimensions using double and
triple integrals and partial differentials. You may have seen the "curly
d" , perhaps
on one of those Maxwell sweatshirts, that represents the "partial"
derivative, which is the rate of change of a function with multiple
dimensions in just one of those dimensions. Thus a vector with three
dimensions has three partial derivatives, one in each direction.
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Now the last piece of the
logical pattern - there are two different forms of change of the vector field
- Divergence and Curl.
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Vector Calculus, developed
soon after Maxwell's great work, greatly simplified the model and the notation,
enabling us to combine his original 20 equations into just four. A single
symbol
pronounced "del" represents the sum of all of these partial
derivatives in all three spatial dimensions. Finding the rate of change of a
field is just a matter of multiplying by the field. But vector multiplication
unlike normal multiplication, generates two different kinds of products not
one - the "dot" product ( ) and the "cross product" ( ). The dot product of and a vector field is a scalar, a
number. It is so important in physics that it has its own name, the
"divergence," because it represents the change in a field generated
by a point source. Like the pincushion, this field diverges radially and
never changing in direction only in magnitude (weakening with distance as the
sphere through which it passes gets larger).
The cross product is a vector that we call
the "curl." Like its name implies, this field is always changing
direction, turning or curling around its source. Returning to our wind
metaphor, if we blow from our mouths, we create a source and that wind goes
straight out, diverging and weakening as it gets further from our face. Wind
in nature, however, is always curling, rotating clockwise around highs and
counterclockwise around lows. We see it in dust devils, tornadoes and on a
larger scale in the satellite images of cloud formations and of hurricanes.
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And 2 kinds of fields:
Electric
Magnetic
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There are two kinds of
fields in electromagnetism, the Electric (E), and the Magnetic (B),
(M is an already overused symbol in physics). Here, then, are the logically
defined left sides of Maxwell's equations; the divergence and curl of the
electric and magnetic fields. There are four, and only four, possible forms.
If the field is fundamental then we should be able to connect this complete
structure to the experience of electricity and magnetism - to the descriptive
laws of Coulomb, Ampere, and Faraday, rewritten in terms of fields rather
than forces. That is what Maxwell did!
1. The first equation connects a diverging electric field
radiating in space with an electric charge. It restates Coulomb's Law.
2. The second defines a diverging magnetic field, which
would be the result of a magnetic "charge." But none has ever been
found and thus the magnetic divergence is set equal to zero.
3. The third links a circulating magnetic field, curling
through space, with an electric field changing with time (an electric
current). It expands Ampere's Law.
4. And the fourth ties a circulating electric field which
would produce a current in a loop of wire, with a magnetic field changing
with time (a moving magnet). It is Faraday's Law.
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This is a Theory
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It is a logical construction
by which a fastening artifact defines and connects sites, to which the sites
and entities of experience can be linked.
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The
aim of science is, on the one hand, a comprehension as complete as possible,
of the connection between sense experiences in their totality, and, on the
other hand, the accomplishment of this aim by the use of a minimum of primary
concepts and relations.
Albert Einstein
This is what a theory looks
like. It is a logical system (the left side of Maxwell's Equations) - defined
in this case by the unique mathematics of a new element, the environment;
which creates and connects a set of logical sites. When these fastening
artifact sites are linked to the empirical sites - the patterns of
experience, then the theory encompasses and connects our experience. When
that happens, the empirical sites become connected, fastened into a new unity
which now brings uniqueness to our knowledge, which liberates us from the
arbitrariness of the experiential names for the sites and the pretense of
their links. It is a very powerful thing. We suddenly have a logical
understanding, a model for our experience which is drawn together by
simplicity and the power of human thought. It is a fastening artifact, the
electromagnetic field, which has four dynamic forms, that now join together
the experiential patterns. Each form of the fastening artifact is connected
to an empirical site (a well-defined collection of experience as described in
each law). And the fastening artifact, in its full glory, now links all of
these descriptive sites together into a unified picture.
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The theory of knowledge has
the same form.
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The theory of knowledge
fits this formula. It is constructed with a new element - the artifact - and
builds a logical structure for sites based on the forms of uniqueness and
thus the uniqueness of artifacts. We then linked those basic forms to the
descriptive Pattern of Knowledge - the empirical sites. And by that
action, the unique artifact brings a fundamental and beautiful unity to this
pattern. No longer are the sites or their names arbitrary. No longer do we
wonder if this pattern is unique. No longer do we wonder why it exists. For
we have a theory, a theory that connects the sites we pulled from experience
by linking them to a unique purely logical form.
There are three and only three forms of
uniqueness: difference, sameness, matching. With these three forms we
construct the three elements of knowledge and only three: entities based on
difference, sites based on sameness, and fasteners based on matching. We can
further differentiate these elements based on uniqueness: the entities into
singular and plural (difference and sameness), the sites into parts and
wholes (difference and sameness), and the fasteners into connections,
relations, and transformations (difference, matching, sameness). We build
knowledge by starting with a unique entity, a template and tool fundamentally
different from any other: a symbol, a universal, an object, an environment,
and now an artifact. We fashion with it our individual entities, from which
we choose a few unique ones to become sites that group and collect the others,
and finally, from a unique site we build a fastener that connects the other
sites together. This is how we construct knowledge. And when we lay out all
of the possible forms, they build the structure of the Pattern of
Knowledge.
I hope that you now find that all of those
mysterious symbols in Maxwell's Equations were worth following. For without
seeing them, it is difficult to really understand how simple and yet powerful
a great theory can be, and how we build them. I apologize to those physicists
who may complain that I have left out some of the fine detail. There is a bit
more pattern that in this short work, I have deleted. But the essence is here
and I hope that you can see why Einstein loved it so; and why, though a full
understanding and more importantly a useful application of a theory may be
complicated, its basic elements are so very simple.
Without a theory the way we name and unify
a pattern of knowledge is quite arbitrary. I had all of the elements of the Pattern
of Knowledge by the mid-1970's, but I did not publish. The names I used
for each of the forms were arbitrary; they came from the best description of
the empirical content and did not represent any theoretical-logical meaning.
I did not publish because I did not want the wrong names, the mislabeling of
these ideas, and so I struggled with the theory to get the names right. When
we create sites outside of theory, we get interesting names like those which
label Quarks - color, flavor, up, down. Without theory we make up names and
hope that they illuminate. Without theory we can not change our vision of
experience. Without theory we do not extend our ideas.
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This started it all for me.
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Before we start to follow
our theory of knowledge into new and uncharted territory, let us linger for
just a moment longer at the wonder of Maxwell. In my favorite passage in all
of the literature of physics and the one that more than any other single
thing enabled me to understand the great leap of Maxwell and the others in
the 1860's, Einstein describes the genius of Maxwell's contribution.
Neglecting
the important individual result which Maxwell's lifework produced in
important departments of physics, and concentrating on the changes wrought by
him in our conception of the nature of physical reality, we may say this:
before Maxwell people conceived of physical reality -- in so far as it is
supposed to represent events in nature -- as material points, whose changes
consist exclusively of motions, which are subject to total differential
equations. After Maxwell they conceived of physical reality as represented by
continuous fields, not mechanically explicable, which are subject to partial
differential equations. This change in the conception of physical reality is
the most profound and fruitful one that has come to physics since Newton....
Einstein & Infeld, The
Evolution of Physics, 1938, Norton
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Theories Take Us Further
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They connect aspects of
experience that are totally unexpected.
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Beyond the sense of
completeness and clarity that Maxwell's unification brought to laws of
electricity and magnetism now directly tied together, his theory also
produced some exciting surprises and totally unexpected results. Not only did
his theory join together Coulomb's, Ampere's, and Faraday's laws, but it made
sense of and integrated many other electrical phenomena including
capacitance. And in one great and totally unexpected result, a direct
extrapolation of these equations - Maxwell joined light to electricity and
magnetism and paved the way not only for an understanding of light, but also
for the development of radio, all of our electronics, and our electromagnetic
communications. Our theory of knowledge, if it is powerful, should extend to
other parts of knowledge that were not included in the development of the
theory and provide us with some wonderful surprises.
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