John von Neumann (1903–1957)

Indeholder "Klara von Neumann: Preface", "Introduction", "Part 1. The Computer", " The Analog Procedure", " The Conventional Basic Operations", " Unusual Basic Operations", " The Digital Procedure", " Markers, Their Combinations and Embodiments", " Digital Machine Types and Their Basic Components", " Parallel and Serial Schemes", " The Conventional Basic Operations", " Logical Control", " Plugged Control", " Logical Tape Control", " The Principle of Only One Organ. for Each Basic Operation", " The Consequent Need/or a Special Memory Organ", " Control by "Control Sequence" Points", " Memory-Stored Control", " Modus Operandi of the Memory-Stored Control", " Mixed Forms of Control", " Mixed Numerical Procedures", " Mixed Representations of Numbers. Machines Built on This Basis Precision", " Reasons for the High (Digital) Precision Requirements", " Characteristics of Modern Analog Machines", " Characteristics of Modern Digital Machines", " Active Components; Questions of Speed", " Number of Active Components Required", " Memory Organs. Access Times and Memory Capacities", " Memory Registers Built from Active Organs", " The Hierarchic Principle for Memory Organs", " Memory Components; Questions of Access", " Complexities of the Concept of Access Time", " The Principle of Direct Addressing", "Part 2. The Brain", " Simplified Description of the Function of the Neuron", " The Nature of the Nerve Impulse", " The Process of Stimulation", " The Mechanism of Stimulating Pulses by Pulses; Its Digital Character", " Time Characteristics of Nerve Response, Fatigue, and Recovery", " Size of a Neuron. Comparisons with Artificial Components", " Energy Dissipation. Comparisons with Artificial Components", " Summary of Comparisons", " Stimulation Criteria", " The Simplest~Elementary Logical", " More Complicated Stimulation Criteria", " The Threshold", " The Summation Time", " Stimulation Criteria for Receptors", " The Problem of Memory within the Nervous System", " Principles for Estimating the Capacity of the Memory in the Nervous System", " Memory Capacity Estimates with These Stipulations", " Various Possible Physical Embodiments of the Memory", " Analogies with Artificial Computing Machines", " The Underlying Componentry of the Memory Need Not Be the Same as That of the Basic Active Organs", " Digital and Analog Parts in the Nervous System", " Role of the Genetic Mechanism in the Above Context", " Codes and Their Bole in the Control of the Functioning of a Machine", " The Concept of a Complete Code", " The Concept of a Short Code", " The Function of a Short Code", " The Logical Structure of the Nervous System", " Importance of the Numerical Procedures", " Interaction of Numerical Procedures with Logic", " Reasons for Expecting High Precision Requirements", " Nature of the System of Notations Employed: Not Digital but Statistical", " Arithmetical Deterioration, Roles of Arithmetical and Logical Depths", " Arithmetical Precision or Logical Reliability, Alternatives", " Other Statistical Traits of the Message System That Could Be Used", " The Language of the Brain Not the Language of Mathematics".

Bogen starter med lidt indledning og lidt forklaring om analoge computere. En differentialanalysator har fx (x+y)/2 og (x-y)/2 som naturlige operatorer i stedet for x+y og x-y. Jeg tror det var en skam at von Neumann ikke nåede at tænke over kvantecomputere.
Han gennemgår kort addition, subtraktion, multiplikation og division som nødvendige for den digitale computer og at det er nemmere i binært, men også sagtens kan gøre decimalt. Præcision i digitale udregninger er meget billig at lave sammenlignet med analog præcision. Nydelig gennemgang af hvordan en digital computer kan opbygges og hvordan registre og memory og eksternt lager kan håndteres.
Derefter kigger han på hjernens opbygning. Han forsøger at bestemme antallet af komponenter, størrelse, energiforbrug, reaktionstid og funktioner. Konklusionen er selvfølgelig at hjernen er meget anderledes end en computer.

Paul Erdős, Paul Halmos, Theodore von Kármán, John G. Kemeny, John von Neumann, George Pólya, Leó Szilárd, Edward Teller og Eugene Wigner blev for sjov kaldt marsmændene, fordi de kom fra et obskurt land (Ungarn) og talte indbyrdes i et uforståeligt sprog og var superintelligente. John von Neumann (28 december 1903 - 8 februar 1957) blev ramt af knoglekræft kort efter at han i starten af 1955 var blevet bedt om at holde en forelæsningsrække "Silliman Lectures" på Yale i forårssemesteret 1956 og selv om han prioriterede artiklerne her meget højt, nåede han ikke i mål.… (meer)

The first part consists of heavily edited versions of von Neumann's famous 1949 lectures given at the University of Illinois. Burks' commentary is interesting though I would like to see the complete lectures.

The second part is a construction of the text von Neumann was working on at the time of his death. This is heavy reading because it's the foundational work of a new field. If one's interest is playing around with CAs there are probably more accessible options.

The book design unfortunately has the figures and schematics for the CA appended instead of intermingled.… (meer)