Thriving Systems Theory and Metaphor-Driven Modeling

Transcription

1 Thriving Systems Theory and Metaphor-Driven Modeling

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3 Leslie J. Waguespack Thriving Systems Theory and Metaphor-Driven Modeling

4 Leslie J. Waguespack Bentley University Waltham, MA USA ISBN e-isbn DOI / Springer London Dordrecht Heidelberg New York British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Control Number: Springer-Verlag London Limited 2010 Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the Copyright, Designs and Patents Act 1988, this publication may only be reproduced, stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers, or in the case of reprographic reproduction in accordance with the terms of licenses issued by the Copyright Licensing Agency. Enquiries concerning reproduction outside those terms should be sent to the publishers. The use of registered names, trademarks, etc., in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant laws and regulations and therefore free for general use. The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or liability for any errors or omissions that may be made. Printed on acid-free paper Springer is part of Springer Science+Business Media (

5 Acknowledgments If the quest for understanding systems quality in this monograph has been challenging, the task of acknowledging all the contributions that have brought me to these ideas is impossible. At the core of this journey was a simple question, How can you tell whether one model of a system is better than another? The question emanates from my teaching of modeling in the object-oriented paradigm over the past two decades. I usually begin my lectures on this topic by declaring, There are no perfect models but there are useful ones and some models are better than others. After dozens of courses teaching OO modeling to undergraduate students, graduate students and practicing software professionals and repeating this declaration countless times, I began the quest to justify the statement with some rational validation greater than my intuition and 45 years of teaching and software development experience. This monograph is my validation effort. My first acknowledgement must go to Christopher Alexander whose writings on physical architecture provide not only the substance on which I have assembled my Thriving Systems Theory, but also on the mode of rational investigation and argument that he models in his four volume treatise on The Nature of Order. That work is both illuminating and inspiring in its approach to expressing knowledge and understanding. I must recognize all those students who were brave enough to allow me to bend their minds with an object-oriented view of the world and describing the things in it. My colleagues at Bentley University granted me sabbatical with the dedicated time to wander and explore the questions of models and systems which led me to Alexander, Lakoff and Brooks. Two of those Bentley colleagues in the Computer Information Systems department generously engaged in countless hours of discussion (and argument) with me over both the content and the mode of expressing the ideas in this monograph: Bill Schiano and David Yates, fast colleagues and dear friends. It is with their continued collaboration I hope to bring these ideas beyond theory into practice. Special thanks to Jennifer Xu for her guidance in the cluster analysis. Two other notable influences are colleagues at the University of South Alabama who arranged for a colloquium visit where I was able to share my questions and test my ambitions for this monograph project: Roy Daigle and Bart Longenecker. v

6 vi Acknowledgments As Lakoff would put it, the layers of metaphors through which I understand systems and software were built up over a lifetime of learning: primary parochial education with the Sisters of the Sacred Heart and a secondary education with the Christian Brothers of Saint John Baptist de La Salle. At the University of Louisiana at Lafayette (formerly the University of Southwestern Louisiana), I earned computer science degrees, a B.S., an M.S. directed by Dr. James R. Oliver and a doctorate under the direction of Professors Bruce Shriver, Wayne Anderson, and Ted Lewis. Endless hours of study and exploration of programming languages, computer architecture, and virtual machine architecture and theory were had with fellow graduate students: Steve Landry, Sam Bullard, Denny Hyams, and Doug Robertson. My years at the United State Air Force Manpower and Personnel Center introduced me to the practical realities and challenges of managing very large databases and trans-global transaction systems. My project management and systems architecture ideas evolved working with Ted Hann, Don Moore, Gary Filipski, and John Newton. My family deserves the majority of my thanks for their patience and support during formation of this work: my loving and devoted spouse, Blanche, and my children: Michael, Patricia, Peter, and Paul, all of whom have plied careers in the computing industry and inspire me with their energy and resilience. Finally, I offer my deepest thanks to my father, Leslie (Sr.), and my mother, Catherine. They are always my first and best teachers in the values of life and living and the font of all the goodness and faith that has showered my life.

7 Contents 1 Introduction The Quest for Great Design: Great Designers Building Buildings and Systems Humans Know and How They Know It A Fusion of Perception, Conception, and Construction A Note of Disclosure to the Reader... Reference... Part I Thriving Systems Theory 2 Christopher Alexander s Nature of Order Order, Complexity, and Human Perception Wholeness and Centers Choices as Centers Wholeness and Center Properties Wholeness and Center Properties Mapped to Modeling Levels of Scale to Stepwise Refinement Strong Centers to Cohesion Boundaries to Encapsulation Alternating Repetition to Extensibility Positive Space to Modularization Good Shape to Correctness Local Symmetries to Transparency Deep Interlock and Ambiguity to Composition of Function Contrast to Identity Gradients to Scale Roughness to User Friendliness Echoes to Patterns The Void to Programmability vii

8 viii Contents 3.14 Simplicity and Inner Calm to Reliability Not Separateness to Elegance Examining the Mapping from Center Properties to Choice Properties Achieving Versus Observing Strength in Choice Properties Stepwise Refinement (To Elaborate) Cohesion (To Factor) Encapsulation (To Encapsulate) Extensibility (To Render Extendable) Modularization (To Modularize) Correctness (To Align) Transparency (To Expose) Composition of Function (To Assemble) Identity (To Identify) Scale (To Focus) User Friendliness (To Accommodate) Patterns (To Pattern) Programmability (To Generalize) Reliability (To Normalize) Elegance (To Coordinate) Modeling Actions: Syntax and Semantics Building Life into Information Systems A Life-Infusing Process for Building Information Systems Applying Alexander s Generative Building Process Complexity and the Improbability of Working Systems Generated Structures: Top-Down Versus Bottom-Up Accident of Implementation: Threat to System Life Peripheral Vision in the Mind s Eye A Vision of Thriving Systems The Field-Effect of Choice Properties Choice Property Coherence Choice Property Clustering Choice Property Cluster Contribution to Wholeness Exploring the Field-Effect of the Clusters Divisibility: The Field-Effect of Cluster A Factorability: The Field-Effect of Cluster B Constructibility: The Field-Effect of Cluster C Confidence: The Field-Effect of Cluster D Predictability: The Field-Effect of Cluster E Usability: The Field-Effect of Cluster F

9 Contents ix Intuitiveness: The Field-Effect of Cluster G Scalability: The Field-Effect of Cluster H Fidelity: The Field-Effect of Cluster I Effectiveness: The Field-Effect of Cluster J Robustness: The Field-Effect of Cluster K Sustainability: The Field-Effect of Cluster L Vitality: The Field-Effect of Cluster M Thriving: The Field-Effect of Cluster N Directing the Field-Effect of Property Clusters The Consequence of Thriving Systems Theory Historical Reverberations... Part II Thriving Systems Theory in Systems Development 7 Metaphorology The Basics of Conceptual Metaphor The Metaphor in Thought: Lakoff s Embodied Mind Lakoff s Embodied Mind Meets Alexander s Nature of Order Metaphors and Patterns Metaphor-Driven Modeling The Nature of Systems The Utility of Modeling Modeling: Crafting Conceptual Metaphors Modeling Essence: Recognizing Accident Quality Through Conceptual Metaphors Protecting Life in System Life Cycles Common Models of System Concerns Model Conjugation and Transparency The Paradox of Modeling Essence in the Now... Reference Metaphor-Driven Systems Engineering Software Engineering Systems Engineering Ordering the Now/Accommodating the Future: Architecture Architecture in Thriving Systems Theory Essence Versus Accident: Bifurcation or Continuum? Information Systems Ecology: Managing Life Checklist for Modeling Thriving Systems

10 x Contents 11 Thriving Systems and Beauty Objective System Quality Assessment Subjective System Quality Assessment The Experience of Quality in Observation Is It Beauty or Is It Thriving? Promoting Life Using the Object-Oriented Paradigm An Ontology of the Object-Oriented Paradigm Modeling Living Structure in the Object-Oriented Paradigm Stepwise Refinement Cohesion Encapsulation Extensibility Modularization Correctness Transparency Composition of Function Identity Scale User Friendliness Patterns Programmability Reliability Elegance Programming Languages Versus Ontology Promoting Life Using the Relational Paradigm An Ontology of the Relational Paradigm Modeling Living Structure in the Relational Paradigm Stepwise Refinement Cohesion Encapsulation Extensibility Modularization Correctness Transparency Composition of Function Identity Scale User Friendliness Patterns Programmability

11 Contents 14 xi Reliability Elegance Programming Languages Versus Ontology Thriving Systems Through Metaphor-Driven Modeling No Perfect Models: Only Useful Ones Processes That Generate Useful Models Useful Models as Enculturated Organisms Modeling the Business Organism Modeling the Business Process Organism Modeling the Software Organism Disambiguating Essence and Accident Models Unfolding as Metaphors The Pace of Life Engineering Thriving Systems Epilogue Index