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I501 – Introduction to Informatics [email protected] http://informatics.indiana.edu/jbollen/I501 Informati cs and computing lecture 2 – Fall 2009 Cybernetics

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Cybernetics. We’ll discuss this week:. McCulloch, W. and W. Pitts [1943], "A Logical Calculus of Ideas Immanent in Nervous Activity". Bulletin of Mathematical Biophysics 5:115-133. - PowerPoint PPT Presentation

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Page 1: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Cybernetics

Page 2: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

McCulloch, W. and W. Pitts [1943], "A Logical Calculus of Ideas Immanent in Nervous Activity". Bulletin of Mathematical Biophysics 5:115-133.

Coutinho, A. [2003]. "On doing science: a speech by Professor Antonio Coutinho". Economia, 4(1): 7-18, jan./jun. 2003.

Heims, S.G. [1991]. The Cybernetics Group. MIT Press. Chapters: 1,2, 11, and 12. Schwartz, M.A. [2008]. "The importance of stupidity in scientific research". Journal of Cell Science, 121: 1771.

We’ll discuss this week:

Page 3: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Informatics:a possible parsing

Complex Systems

Data & Search

Data Mining

HCID

Social Informatics

Security

Bio-

Chem-

Geo-

Music-

Health-

towards problem solving beyond computing into the natural and social synthesis of information technology

Page 4: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Pre-cybernetics“Cerebral inhibition meeting” New York City, May 1942

Organized by Frank Freemont-Smith of the Josiah Macy Jr. Foundation Social Sciences: Lawrence Frank, Margaret Mead and Gregory Bateson Sciences: Warren McCulloch and Arturo Rosenblueth

Result Rosenblueth’s presentation of concepts from Norbert Wiener and Julien Bigelow

Homeostasis, purposeful action (goal-direction), aiming A new paradigm of interdisciplinary research?

Goal-directed actions Controversial: explaining actions in terms of future events, violating cause

and effect Teleological mechanisms

Circular causality requiring negative feedback (postulated to be very common) Present state becomes input for action at next moment: State-determined

systems The mathematics were accessible

Page 5: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Post-WWII science: Macy Meetings 1946-1953

The Feedback Mechanisms and Circular Causal Systems in Biology and the Social Sciences

March 1946 (10 meetings between 1946 and 1953) Interdisciplinary

Since a large class of ordinary phenomena exhibit circular causality, and the mathematics is accessible, let’s look at them with a war-time team culture

Participants John Von Neumann, Leonard Savage, Norbert Wiener, Arturo Rosenblueth, Walter Pitts,

Margaret Mead, Heinz von Foerster, warren McCulloch, Gregory Bateson, Claude Shannon, Ross Ashby, etc.

Synthetic approach Engineering-inspired: amplifiers, negative feedback, feedback circuits Supremacy of mechanism

All can be axiomatized and computed Mculloch & Pitts’ and Von Neumann’s work was major influence

Page 6: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Alan Turing: 1935-1954pop science hero for Turing test

“I propose to consider the question, "Can machines think?" This should begin with definitions of the meaning of the terms "machine" and "think." The definitions might be framed so as to reflect so far as possible the normal use of the words, but this attitude is dangerous, If the meaning of the words "machine" and "think" are to be found by examining how they are commonly used it is difficult to escape the conclusion that the meaning and the answer to the question, "Can machines think?" is to be sought in a statistical survey such as a Gallup poll. But this is absurd. Instead of attempting such a definition I shall replace the question by another, which is closely related to it and is expressed in relatively unambiguous words. The new form of the problem can be described in terms of a game which we call the 'imitation game." It is played with three people, a man (A), a woman (B), and an interrogator (C) who may be of either sex. The interrogator stays in a room apart front the other two. The object of the game for the interrogator is to determine which of the other two is the man and which is the woman. He knows them by labels X and Y, and at the end of the game he says either "X is A and Y is B" or "X is B and Y is A.”

Jack copeland

Page 7: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

How to fail the Turing test:

Page 8: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Alan Turing: 1935-1954Universal Turing Machine

In 1935, at Cambridge University, Turing invented the principle of the modern computer: Universal Turing Machine. Abstract digital computing machine

consisting of a limitless memory and a scanner that moves back and forth through the memory, symbol by symbol, reading what it finds and writing further symbols (Turing [1936]).

The actions of the scanner are dictated by a program of instructions that is stored in the memory in the form of symbols.

Note: Turing machine is mathematical construct to study/define notions of computability

Page 9: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Turing MachineFrom : A. M. Turing (1936) On Computable numbers… Proceedings of the London Mathematical Society.

We have said that the computable numbers are those whose decimals are calculable by finite means. This requires rather more explicit definition. No real attempt will be made to justify the definitions given until we reach §9. For the present I shall only say that the justification lies in the fact that the human memory is necessarily limited.

We may compare a man in the process of computing a real number to a machine which is only capable of a finite number of conditions q1, q2, ..., qR which will be called “m-configurations”. The machine is supplied with a “tape”, (the analogue of paper) running through it, and divided into sections (called “squares”) each capable of bearing a “symbol”. At any moment there is just one square, say the r-th, bearing the symbol S(r) which is “in the machine”. We may call this square the “scanned square”. The symbol on the scanned square may be called the “scanned symbol”. The “scanned symbol” is the only one of which the machine is, so to speak, “directly aware”. However, by altering its m-configuration the machine can effectively remember some of the symbols which it has “seen” (scanned) previously. The possible behaviour of the machine at any moment is determined by the m-configuration qn and the scanned symbol S(r). This pair qn, S(r) will be called the “configuration”: thus the configuration determines the possible behaviour of the machine. In some of the configurations in which the scanned square is blank (i.e. bears no symbol) the machine writes down a new symbol on the scanned square: in other configurations it erases the scanned symbol. The machine may also change the square which is being scanned, but only by shifting it one place to right or 1eft. In addition to any of these operations the m-configuration may be changed. Some of the symbols written down will form the sequence of figures which is the decimal of the real number which is being computed. The others are just rough notes to “assist the memory”. It will only be these rough notes which will be liable to erasure.

It is my contention that these operations include all those which are used in the computation of a number.

Page 10: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Turing machine

10 0 1 1 1 0 1100

S(r)= {0,1}m-configuration= {q1,…}(machine state)

wrt mov nxq wrt mov nxq wrt mov nxq...

0 1 L q2 0 R q1 0 L q21 0 R q4 1 R q3 1 L q1

S(r)=

q1 q2 q3

(state transition table)

{L,R} += position t{0,1} = write value

r

Page 11: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Universal Turing machine State transition table ITSELF can be stored on dedicated section of tape!

Hence “Universal Turing Machine”: all possible turing machines can be described as strings on tape

Data and program are encoded on same substrate, in same manner Later instantiated by Von Neumann as “stored program concept” "We are trying to build a machine to do all kinds of different things

simply by programming rather than by the addition of extra apparatus," (1947)

Demonstrating functional analogy (mathematical isomorphism) with UTM is a big deal Defines mathematical constraints Cf. Wolfram’s announcement

(http://www.wolframscience.com/prizes/tm23/background.html)

Page 12: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Is Lego a UTM? ;-)

Page 13: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Is your brain a universal turing machine?

McCulloch, W. and W. Pitts [1943], "A Logical Calculus of Ideas Immanent in Nervous Activity". Bulletin of Mathematical Biophysics 5:115-133. A finite network of binary neuron/switches ~ Turing

machine program Neurons as basic computing unit of the brain Circularity is essential for memory (closed loops to

sustain memory) Brain (mental?) function as computing

Others at Macy Meeting emphasized other aspects of brain activity Chemical concentrations and field effects (not digital) Ralph Gerard and Fredrik Bremmer

Page 14: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Babbage difference engine (1822)

Babbage analytical engine (turing complete!)

Some early contenders (not electronic, not digital, or not Turing complete)

Page 15: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Turing bombe:Enigma Cracker (1940-

1945)

Some early contenders (not electronic, not digital, not Turing complete)

Page 16: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Colossus Mark 1,2 Electromechanical code decoders Paper tape input/output Internal simulation of encryption device No. 2 using vacuum tubes

Some early contenders (not electronic, not digital, not Turing complete)

Page 17: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Some early contenders (not electronic, not digital, not Turing complete)

Konrad Zuse Z1,2,3 (1941) Fully program-controled Using electro-mechanical relays

Harvard Mark I (1944) Drive-shafts & switches Separation data-program 765,000 components 4500 kg

http://www.youtube.com/watch?v=vEx4t71jca4

Page 18: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

The vacuum tube:an audiophile’s delight, a turing machine builder’s nightmare

Vacuum tubes: Invented by American physicist Lee De Forest in 1906. Electricity heats a filament inside the tube. Freed electrons

travel through vacuum from one pole to the next. Grid sits between poles. Small charges on grid can block large currents: tube = amplifier or switch.

the presence of current represented a one. Punched-card input and output

Boxes & truck load Beware of “syntax error”

Storage of all those vacuum tubes and the machinery required to keep them cool: entire floors of building

Page 19: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

ENIAC (1945)Electronic Numerical Integrator and Computer

First fully programmable, electronic digital computer to be built in the U.S. Electrical Numerical Integrator and Computer University of Pennsylvania, for the Army Ordnance Department, by J.

Presper Eckert and John Mauchly. Used decimal digits instead of binary ones Nearly 18,000 vacuum tubes for switching. Far from general-purpose: The primary function was calculation of

tables used in aiming artillery. ENIAC was not a stored-program computer, and setting it up for a

new job involved reconfiguring the machine by means of plugs and switches.

Page 20: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

ENIAC 1945

Computerbug

Page 21: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

ENIAC 1945

Page 22: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

ENIAC 1945

Page 23: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

John von Neumann Emphasized stored-program concept for electronic computing (machine

modifying its own program) At first Macy Meeting

Compared neurons to binary switches “The Computer and the Brain”: bio-inspired design Influenced by McCulloch & Pitts, Turing High impact on cybernetics

Lead the ENIAC (1944-1945) group to the EDVAC (1952) Von Neumann made the concept of a high-speed stored-program

digital computer widely known through his writings and public addresses: ‘von Neumann machines’.

von Neumann architecture: The separation of data and program (storage )from the processing unit = architecture still in use today.

Prolific scientist Father of game theory, cellular automata, Cybernetics, Artificial

Intelligence See book: Aspray, William. 1990. John von Neuman and the Origins of

Modern Computing. Cambride, Mass.: MIT Press.

Page 24: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

EDSAC 1949(Electronic Delay Storage Automatic Calculator (Cambridge)

_Stored programGeneral purpose

Page 25: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

EDVAC 1949(Electronic Delay Variable Automatic Calculator (Cambridge)

_Descendent of ENIACStored programbinary

Page 26: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

IAS Machine 1942-1952First electronic digital computer with 40 bit word (IAS, Princeton)

_

First to combine data and program? See Manchester Manchester Small Scale Experimental Machine

5.1KB memory!Many descendants, among them the MANIAC at Los Alamos Scientific Laboratory: hydrogen bombs and chess.

Page 27: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Meanwhile at the MACY meetings:Norbert Wiener and Arturo Rosenblueth:

Goal-directed behavior and negative feedback (control) Homeostasis and circular causality

In machines and biology Automata Theory Communication

The fundamental idea is the message, even though the message may not be sent by man and the fundamental element of the message is the decision” (Norbert Wiener)

Information and Communication Theory Natural semiotics (McCulloch and others later get into Peircean Semiotics) “functional equivalence” of systems (general systems) Bio-inspired mathematics and engineering and computing/mechanism-inspired

biology and social science

Page 28: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Macy meetings:other key concepts

Gregory Bateson and Margaret Mead Homeostasis and circular causality in society Transvestite ceremony to diffuse aggressive action in

Iatmul culture Learning and evolution

Can a computer learn to learn? A new organizing principle for the social sciences (control

and communication) As much as evolution was for Biology

Lawrence Frank The new interdisciplinary concepts needed a new kind of

language Higher generality than what is used in single topic

disciplines A call for a science of systems

Yehoshua Bar-Hillel Optimism of a new (cybernetics and information) age “A new synthesis […] was destined to open new vistas on

everything human to help solve many of the disturbing open problems concerning man and humanity”.

Page 29: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Cybernetics as a discipline Norbert Wiener’s book had huge impact

Coined the term “Cybernetics” Κυβερνήτης (kybernētēs, steersman, governor, pilot, or rudder — the

same root as government). Overoptimism?

“Those of us who have contributed to the new science of cybernetics, stand in a moral position which is, to say the least, not very comfortable. We have contributed to the initiation of a new science which, as I have said, embraces technical developments with great possibilities for good and for evil”. [1948]

A “premature delivery” (Ralph Gerard)? “excessive optimism and a misunderstanding of the nature of scientific

achievement.” (Gregory Bateson) ?...

Page 30: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Cybernetics as a discipline Death by its own success

Success meant adoption by many fields But not a highly successful discipline in itself

Most practitioners became marginal in their original disciplines The price of interdisciplinary research in Academia? Successful descendents in more interdisciplinary settings outside of

academia Government labs (e.g. Los Alamos National Laboratory) Private Institutes (e.g. Santa Fe Institute)

What about informatics as a field? Finally academia accepting the reality of the information age in

society?... Need to define identity, lest same trap of interdisciplinary

Page 31: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Lives on through its effects on science and language

Learning as information transmission Computer is prevalent analogy for understanding life and cognition “Feedback” is now general terms to mean information about outcomes

(“terugkoppeling”) Shift fom individualism and cause & effect, to circular causation and social

interaction “Programmed” behavior Society and organisms as systems Wiener’s prediction of a second industrial revolution centered on

communication, control, computation, information, and organization was correct Abundance of technology and mass production of communication devices

Grew out of the ideas first reported by the cyberneticians Informatics is an offspring of cybernetics

Page 32: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Informatics:a possible parsing

Complex Systems

Data & Search

Data Mining

HCID

Social Informatics

Security

Bio-

Chem-

Geo-

Music-

Health-

towards problem solving beyond computing into the natural and social synthesis of information technology

Page 33: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Created new fields analytical in methodology synthetic interdisciplinary concepts useful in constituent fields

Cybernetics

AI ORCS

Page 34: Cybernetics

I501 – Introduction to Informatics

[email protected]://informatics.indiana.edu/jbollen/I501

Informatics and computing

lecture 2 – Fall 2009

Klir, G.J. [2001]. Facets of systems Science. Springer. Chapters: 1 and 2

Rosen, R. [1986]. "Some comments on systems and system theory". Int. J. of General Systems, 13: 1—3.

Ashby, W.R.[1956]. An Introduction to Cybernetics, Chapman & Hall, London, Chapter 1.

Readings for next week:(General Systems Theory)