前辅文
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 for 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 Role 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