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Transcript
THE COMPLEXITY OF SCIENCE AND
THE SCIENCE OF COMPLEXITY: HOW
TO SURVIVE IN
A SELF-REFERENTIAL WORLD
DON MIKULECKY
PROFESSOR OF PHYSIOLOGY
VIRGINIA COMMONWEALTH
UNIVERSITY
http://views.vcu.edu/~mikuleck/
WHAT IS COMPLEXITY?




TOO MANY DEFINITIONS, SOME
CONFLICTING
OFTEN INTERCHANGED WITH
“COMPLICATED”
HAS A REAL MEANING BECAUSE IT IS
BEING USED SO FREQUENTLY
THAT MEANING ITSELF IS COMPLEX(THIS
IS SELF-REFERENTIAL: HOW CAN WE
DEFINE “COMPLEX” USING “COMPLEX”?)
THE CENTURY OF
COMPLEXITY?

Complexity Digest 2001.10 March-052001

"I think the next century will be the
century of complexity."
Stephen Hawking

CIRCULARITY (SELF-REFERENCE)
CAUSES PROBLEMS FOR LOGIC AND
SCIENCE




I AM A CORINTHIAN
ALL CORINTHIANS ARE LIARS
OR
“THE STATEMENT ON THE OTHER
SIDE IS FALSE”-ON BOTH SIDES
CAN WE GET RID OF SELFREFERENCE, THAT IS, CIRCULARITY?




IT HAS BEEN TRIED
IT FAILED
THE ALTERNATIVE IS TO “GO
AROUND” IT – THAT IS TO IGNORE
CASES WHERE IT POPS UP
WHAT IF IT IS VERY COMMON?
SELF-REFERENCE, CIRCULARITY
AND THE GENOME
REPLICATION
TRANSCRIPTION
HOMEOSTASIS
WHERE DO CELLS COME
FROM?





DNA?
GENES?
PROTEINS?
OTHER CELLS?
SPONTANEOUS GENERATION?
THE CELL THEORY

CELLS COME FROM OTHER CELLS
WHAT IS SCIENCE?




ALSO HAS MANY DEFINTIONS
SOME OF THESE ARE IN CONFLICT
SCIENCE IS A BELIEF STRUCTURE
SCIENCE OF METHOD VS SCIENCE
OF CONTENT
WHY IS SCIENCE A BELIEF
STRUCTURE?


WHAT IS THE PROCESS BY WHICH
WE “KNOW” THINGS ABOUT THE
WORLD?
WE ALL MAKE MODELS IN ORDER
TO FUNCTION IN THE REAL WORLD
THE MODELING RELATION: A
MODEL OF HOW WE MAKE
MODELS
NATURAL
SYSTEM
ENCODING
CAUSAL
EVENT
IMPLICATION
DECODING
NATURAL
SYSTEM
FORMAL
SYSTEM
FORMAL
SYSTEM
WE HAVE A USEFUL
MODEL WHEN
ARE SATISFACTORY WAYS OF “UNDERSTANDING”
THE CHANGE IN THE WORLD “OUT THERE”
THE MODELING RELATION: A
MODEL OF HOW WE MAKE
MODELS
NATURAL
SYSTEM
ENCODING
CAUSAL
EVENT
MANIPULATION
DECODING
NATURAL
SYSTEM
FORMAL
SYSTEM
FORMAL
SYSTEM
WHAT “TRADITIONAL SCIENCE”
DID TO THE MODELING
RELATION
FORMAL
SYSTEM
NATURAL
MANIPULATION
SYSTEM
CAUSAL
EVENT
FORMAL
SYSTEM
NATURAL
SYSTEM
WHAT “TRADITIONAL SCIENCE”
DID TO THE MODELING
RELATION
FORMAL
NATURAL
SYSTEM
SYSTEM
MANIPULATION
FORMAL
NATURAL
SYSTEM
SYSTEM
THE SCIENTIFIC MODELING
RELATION: A MODEL OF HOW WE
DO SCIENCE
NATURAL
SYSTEM
FORMULA
FORMAL
SYSTEM
MANIPULATION
EXPERIMENT
DATA FITTING
NATURAL
SYSTEM
FORMAL
SYSTEM
WHY ARE THERE SO MANY
DEFINITIONS OF COMPLEXITY?



SCIENTISTS FOCUS ON THE
FORMAL DESCRIPTION RATHER
THAN THE REAL WORLD
THE REAL WORLD IS COMPLEX
FORMAL SYSTEMS COME IN
VARYING SHADES AND DEGREES OF
COMPLEXITY OR COMPLICATION
WHY WHAT “TRADITIONAL
SCIENCE” DID TO THE
MODELING RELATION MADE THE
PRESENT SITUATION
INEVITABLE:

THE “REAL WORLD” REQUIRES
MORE THAN ONE “FORMAL SYSTEM”
TO MODEL IT (THERE IS NO
“UNIVERSAL MODEL”)
WHY WHAT “TRADITIONAL
SCIENCE” DID TO THE
MODELING RELATION MADE THE
PRESENT SITUATION
INEVITABLE:

WE MORE OR LESS FORGOT THAT
THERE WAS AN ENCODING AND
DECODING
WHY WHAT “TRADITIONAL
SCIENCE” DID TO THE
MODELING RELATION MADE THE
PRESENT SITUATION
INEVITABLE:

WE ARE TOO AFRAID OF “BELIEFS”
(SCEPTICISM IS “IN”)

WE DEVELOPED THE MYTH OF
“OBJECTIVITY”
WHY WHAT “TRADITIONAL
SCIENCE” DID TO THE QUESTION
MADE THE PRESENT SITUATION
INEVITABLE:


THE MACHINE METAPHOR TELLS US
TO ASK “HOW?”
REAL WORLD COMPLEXITY TELLS
US TO ASK “WHY?”
THE FOUR BECAUSES: WHY A
HOUSE?




MATERIAL: THE STUFF IT’S MADE OF
EFFICIENT: IT NEEDED A BUILDER
FORMAL: THERE WAS A BLUEPRINT
FINAL: IT HAS A PURPOSE
WHY IS “OBJECTIVITY” A MYTH?
(OR: WHY IS SCIENCE A BELIEF
STRUCTURE)


THE FORMAL SYSTEM DOES NOT AND CAN
NOT TELL US HOW TO ENCODE AND
DECODE. (MODELING IS AN ART!)
THE FORMAL SYSTEM DOES NOT AND CAN
NOT TELL US WHEN THE MODEL WORKS,
THAT IS A JUDGEMENT CALL EVEN IF
OTHER FORMALISMS ARE EMNLISTED TO
HELP (FOR EXAMPLE: STATISTICS)
WHAT ARE SOME OF THE THINGS THAT
MAKE “COMPLEXITY THEORY” NECESSARY?
(WHAT HAS “TRADITIONAL SCIENCE”
FAILED TO EXPLAIN?)




WHY IS THE WHOLE MORE THAN
THE SOME OF THE PARTS?
SELF-REFERENCE AND
CIRCULARITY
THE LIFE/ORGANISM PROBLEM
THE MIND/BODY PROBLEM
WHY IS THE WHOLE MORE THAN
THE SOME OF THE PARTS?


BECAUSE REDUCING A REAL SYSTEM TO
ATOMS AND MOLECULES LOOSES
IMPORTANT THINGS THAT MAKE THE
SYSTEM WHAT IT IS
BECAUSE THERE IS MORE TO REALITY
THAN JUST ATOMS AND MOLECULES
(ORGANIZATION, PROCESS, QUALITIES,
ETC.)
SELF-REFERENCE AND
CIRCULARITY


THE “LAWS” OF NATURE THAT
TRADITIONAL SCIENCE TEACHES ARE
ARTIFACTS OF A LIMITED MODEL
THE REAL “RULES OF THE GAME” ARE
CONTEXT DEPENDENT AND EVER
CHANGING- THEY MAKE THE CONTEXT
AND THE CONTEXT MAKES THEM (SELFREFERENCE)
EXAMPLE: THE
LIFE/ORGANISM PROBLEM





LIFE IS CONSISTENT WITH THE LAWS OF
PHYSICS
PHYSICS DOES NOT PREDICT LIFE
LIVING CELLS COME FROM OTHER
LIVING CELLS
AN ORGANISM MUST INVOLVE CLOSED
LOOPS OF CAUSALITY
LIFE DOES INVOLVE PURPOSE
EXAMPLE: THE
MIND/BODY PROBLEM



HOW CAN THE MIND MODEL
ITSELF?
AM I CONSCIOUS?
HOW DOES THE BRAIN PRODUCE
CONSCIOUSNESS, SELF
AWARENESS, ETC.?
CAN WE DEFINE COMPLEXITY?
Complexity is the property of a real world
system that is manifest in the inability of any
one formalism being adequate to capture all
its properties. It requires that we find
distinctly different ways of interacting with
systems. Distinctly different in
the sense that when we make successful
models, the formal systems needed to
describe each distinct aspect are NOT
derivable from each other
The Mexican sierra [fish] has "XVII-15-IX" spines
in the dorsal fin. These can easily be counted ...
We could, if we wished, describe the sierra thus:
"D. XVII-15-IX; A. II-15-IX," but we could see the
fish alive and swimming, feel it plunge against
the lines, drag it threshing over the rail, and
even finally eat it. And there is no reason why
either approach should be inaccurate.
Spine-count description need not
suffer because another approach is also used.
Perhaps, out of the two approaches we thought
there might emerge a picture more complete and
even more accurate that either alone could
produce.
-- John Steinbeck, novelist,
with Edward Ricketts, marine biologist (1941)
CONCLUSIONS





THE REAL WORLD IS COMPLEX
THE WORLD OF “SIMPLE MECHANISMS” IS A
SURROGATE WORLD CREATED BY TRADITIONAL
SCIENCE
WE ARE AT A CROSSROADS: A NEW WORLDVIEW
IS NEEDED
THERE WILL ALWAYS BE RISK ASSOCIATED WITH
ATTEMPTS TO PROGRESS
YOUR CRYSTAL BALL MAY BE AS GOOD AS MINE
OR BETTER
POST SCRIPT




WE LIVE IN A WORLD DOMINATED BY COMPUTERS
MOST COMPLEXIFIERS BELIEVE THAT
COMPLEXITY IS SOMETHING WE CAN DEAL WITH
ON THE COMPUTER
THIS NOTION OF COMPLEXITY FOCUSES ON THE
MECHANICAL ASPECTS OF THE REAL WORLD
WHAT MAKES THE REAL WORLD COMPLEX IS ITS
NON-COMPUTABILITY