🕸Systems Engineering: Systems Thinking (Definitions)

"Systems thinking is a discipline for seeing the 'structures' that underlie complex situations, and for discerning high from low leverage change. That is, by seeing wholes we learn how to foster health. To do so, systems thinking offers a language that begins by restructuring how we think." (Peter Senge, "The Fifth Discipline", 1990)

"Systems thinking is a framework for seeing interrelationships rather than things, for seeing patterns rather than static snapshots. It is a set of general principles spanning fields as diverse as physical and social sciences, engineering and management." (Peter Senge, "The Fifth Discipline", 1990)

"A school of thought that focuses on recognizing the interconnections between the parts of a system and synthesizing them into a unified view of the whole." (Virginia Anderson & Lauren Johnson, "Systems Thinking Basics: From Concepts to Casual Loops", 1997)

"Systems thinking means the ability to see the synergy of the whole rather than just the separate elements of a system and to learn to reinforce or change whole system patterns." (Richard L Daft, "The Leadership Experience", 2002)

"A concept for describing a way of helping people view systems from a wide perspective, seeing overall structures, patterns and cycles in subsystems, rather than seeing only specific events in the main system." (Thomas Hansson, "Communication and Relation Building in Social Systems", 2008)

"Systems thinking is a mental discipline and framework for seeing patterns and interrelationships." (Richard L Daft, "The Leadership Experience", 2008) 

"A manner of thinking that takes into account how the things being studied relate and connect to each other. A key idea embedded in systems theory is that it can assist us in understanding of phenomena and that its holistic emphasis will promote orderly thinking. It is an apt approach to use when thinking about complex issues and interactions." (Deborah W Proctor, "Accessibility of Technology in Higher Education", 2009)

"An approach to analysis, based on the insight that components of a system or (sub)systems may act differently when isolated from the interacting environment and hence the basic concept for studying systems in a holistic way as a supplement to traditional reductionistic techniques." (Herwig Ostermann et al, "Benchmarking Human Resource Information Systems", 2009)

"Critical to this definition is the term ‘interaction’, in that systems thinking is a form of analysis that goes beyond specific causes and effects to the discernment of hidden patterns of behaviors and underlying systemic interrelationships." (Gerald Goodman & Anne Selcer, "Systems Thinking as the Model for Educating Future Healthcare Managers in Information Technology", 2009)

"Is thinking holistically and conscientiously about the world by focusing on the interaction of the parts and their influence within and over the system." (Kambiz E Maani, "Systems Thinking and the Internet from Independence to Interdependence", 2009)

"A holistic concept of tackling problems and events by taking into account the larger scope in the complete environment." (Nashon J Adero et al, "Flow-Based Structural Modelling and Dynamic Simulation of Lake Water Levels", 2011)

"An approach that emphasizes the interconnected nature of the different components that make up a system. Thus, to understand a problem with performance in an organization, you must analyze the whole organizational system not just the component (process, unit or individual) that on the surface seems to be the root of the problem." (Ian Douglas, "Organizational Needs Analysis and Knowledge Management", 2011)

"An approach to understanding the interconnectedness of components when grouped together in order to solve a problem and how the grouped components behave under different stimuli." (Kyle G. Gipson & Robert J Prins, "Materials and Mechanics: A Multidisciplinary Course Incorporating Experiential, Project/Problem-Based, and Work-Integrated Learning Approaches for Undergraduates", 2015)

"In a system dynamics context, a way of thinking based on system dynamics. It is also used to mean system dynamics analyses without quantitative definitions. It focuses on feedback loop structure in order to forecast the direction of performance and find pertinent elements for controlling systems. This is also called qualitative system dynamics." (Yutaka Takahashi, "System Dynamics", 2015)

"Systems thinking is a discipline or process that considers how individual elements interact with one another as part of a whole entity. As an approach to solving problems, systems thinking uses relationships among individual elements and the dynamics of these relationships to explain the behavior of systems such as an ecosystem, social system, or organization." (Karen L Higgins, "Economic Growth and Sustainability: Systems Thinking for a Complex World", 2015)

"The process and understanding of how items influence one another within a whole." (Reginald Wilson, "Outage Analysis and Maintenance Strategies in Hydroelectric Production", 2015)

"A perspective and approach to problem-solving that emphasizes understanding the world in terms of dynamic systems, the interrelationships among elements of systems, and how systems influence each other." (Elisabeth R Gee Kelly M Tran, "Video Game Making and Modding", 2016)

"A relevant scientific instrumentarium, based on principles of General Systems Theory, which uses the systems ideas in order to research and solve complex strategic problems/problem situations." (Dejana Zlatanović et al, "Higher Education Institutions as Viable Systems: A Cybernetic Framework for Innovativeness", 2020)

"The process of understanding how things influence one another. It refers rather to seeing overall structures, patterns and cycles in systems, and the connections between them, than specific events in the system." (The KPI Institute)

🕸Systems Engineering: System Dynamics (Definitions)

"A field of study that includes a methodology for constructing computer simulation models to achieve better under-standing of social and corporate systems. It draws on organizational studies, behavioral decision theory, and engineering to provide a theoretical and empirical base for structuring the relationships in complex systems." (Virginia Anderson & Lauren Johnson, "Systems Thinking Basics: From Concepts to Casual Loops", 1997) 

"A methodology for studying and managing complex feedback systems, such as one finds in business and other social systems." (Lars O Petersen, "Balancing the Capacity in Health Care", 2008)

"System dynamics is a top-down approach for modelling system changes over time. Key state variables that define the behaviour of the system have to be identified and these are then related to each other through coupled, differential equations." (Peer-Olaf Siebers & Uwe Aickelin, "Introduction to Multi-Agent Simulation", 2008) 

"A continuous simulation of systems exhibiting feedback loops. The feedbacks can either intensify activities of the system (positive feedback) or slow them down and stabilize the system (negative feedback)." (Nikola Vlahovic & Vlatko Ceric, "Multi-Agent Simulation in Organizations: An Overview", 2009)

"Is a scientific tool which embodies principles from biology, ecology, psychology, mathematics, and computer science to model complex and dynamic systems." (Kambiz E Maani, "Systems Thinking and the Internet from Independence to Interdependence", 2009)

"System dynamics is an approach to understanding the behaviour of over time. It deals with internal feedback loops and time delays that affect the behaviour of the entire system. It also helps the decision maker untangle the complexity of the connections between various policy variables by providing a new language and set of tools to describe. Then it does this by modeling the cause and effect relationships among these variables." (Raed M Al-Qirem & Saad G Yaseen, "Modelling a Small Firm in Jordan Using System Dynamics", 2010)

[system dynamics simulation:] "A dynamic form of visualization that combines causal loop diagrams and stock and flow diagrams to create a simulation of the workings of a system from one point in time to another." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"An approach for capturing the complex inter- and intra- dependencies that characterize systems, including feedback over time." (Howard Passell, "Collaborative, Stakeholder-Driven Resource Modeling and Management", 2011)

This studies the non-linear interaction of systems of many connected equations. The approach is based on differential equations. It describes the dynamical properties of a whole system using internal negative and positive feedback loops as well as the use of stocks and flows. (Martin Neumann, "An Epistemological Gap in Simulation Technologies and the Science of Society", 2011)

"A simulation-modelling approach to understand the structure and behaviour of complex dynamic systems over time." (Jaime A Palma-Mendoza, "Hybrid SD/DES Simulation for Supply Chain Analysis", 2014)

"A systems simulation methodology to study complex dynamic behavior of industrial and social systems based on control engineering and cybernetics." (Michael Mutingi & Charles Mbohwa, 2014)

[system dynamics:] "The interactions of connected and interdependent components, which may cause change over time and give rise to interconnected risks; emerging, unforeseeable issues; and unclear, disproportional cause-and-effect relationships." (Project Management Institute, "Navigating Complexity: A Practice Guide", 2014)

"A continuous simulation of systems exhibiting feedback loops. The feedbacks can either intensify activities of the system (positive feedback) or slow them down and stabilize the system (negative feedback)." (Nikola Vlahovic & Vlatko Ceric, "An Overview of Multi-Agent Simulation in Organizations", 2015)

"System Dynamics is a dynamic modelling approach at system level which is primarily used to understand interconnected systems and their evolution over time. Basic elements to represent the systems are internal feedback loops as well as stocks and flows." (Catalina Spataru et al, "Multi-Scale, Multi-Dimensional Modelling of Future Energy Systems", 2015)

"System dynamics [...] uses models and computer simulations to understand behavior of an entire system, and has been applied to the behavior of large and complex national issues. It portrays the relationships in systems as feedback loops, lags, and other descriptors to explain dynamics, that is, how a system behaves over time. Its quantitative methodology relies on what are called 'stock-and-flow diagrams' that reflect how levels of specific elements accumulate over time and the rate at which they change. Qualitative systems thinking constructs evolved from this quantitative discipline." (Karen L Higgins, "Economic Growth and Sustainability: Systems Thinking for a Complex World", 2015)

"A simulation technique based on the solution of differential equations, in which the status variables of a system vary with continuity." (Lorenzo Damiani et al, "Different Approaches for Studying Interruptible Industrial Processes: Application of Two Different Simulation Techniques", 2016)

"A technique que allow to obtain models to explore possible futures or scenarios and ask 'what if' questions in complex situations." (Ruth R Gallegos, "Using Modeling and Simulation to Learn Mathematics", Handbook of Research on Driving STEM Learning With Educational Technologies, 2017)

"A method through which the dynamic behaviour of a complex system over time can be better understood by taking into account internal feedback and time delays." (Henry Xu & Renae Agrey, "Major Techniques and Current Developments of Supply Chain Process Modelling", 2018)

"Computer-aided methodology able to represent the causal structure of a system through stock-and-flow feedback structures and computer simulations regarding the accumulation of materials, information, people, and money." (Francesca Costanza, "Governing Patients' Mobility to Pursue Public Value: A System Dynamic Approach to Improve Healthcare Performance Management", 2018)

"The basis of system dynamics is to understand how system structures cause system behavior and system events." (Arzu E Şenaras, "A Suggestion for Energy Policy Planning System Dynamics", 2018)

🕸Systems Engineering: Systems Theory (Just the Quotes)

"Linking the basic parts are communication, balance or system parts maintained in harmonious relationship with each other and decision making. The system theory include both man-machine and interpersonal relationships. Goals, man, machine, method, and process are woven together into a dynamic unity which reacts." (George R Terry, "Principles of Management", 1960)

"Industrial production, the flow of resources in the economy, the exertion of military effort in a war theater-all are complexes of numerous interrelated activities. Differences may exist in the goals to be achieved, the particular processes involved, and the magnitude of effort. Nevertheless, it is possible to abstract the underlying essential similarities in the management of these seemingly disparate systems." (George Dantzig, "Linear programming and extensions", 1963) 

"The aim of systems theory for business is to develop an objective, understandable environment for decision making; that is, if the system within which managers make the decisions can be provided as an explicit framework, then such decision making should be easier to handle." (Richard A Johnson et al, "Systems Theory and Management", Management Science Vol. 10 (2), 1964)

"System theory is basically concerned with problems of relationships, of structure, and of interdependence rather than with the constant attributes of objects. In general approach it resembles field theory except that its dynamics deal with temporal as well as spatial patterns. Older formulations of system constructs dealt with the closed systems of the physical sciences, in which relatively self-contained structures could be treated successfully as if they were independent of external forces. But living systems, whether biological organisms or social organizations, are acutely dependent on their external environment and so must be conceived of as open systems." (Daniel Katz, "The Social Psychology of Organizations", 1966)

"Clearly, if it is possible to have a self-regulating system that implicitly arranges its own stability, then this is of the keenest management interest." (Anthony S Beer, "Management Science", 1968) 

"The management of a system has to deal with the generation of the plans for the system, i. e., consideration of all of the things we have discussed, the overall goals, the environment, the utilization of resources and the components. The management sets the component goals, allocates the resources, and controls the system performance." (C West Churchman, "The Systems Approach", 1968)

"Perhaps the most important single characteristic of modern organizational cybernetics is this: That in addition to concern with the deleterious impacts of rigidly-imposed notions of what constitutes the application of good 'principles of organization and management' the organization is viewed as a subsystem of a larger system(s), and as comprised itself of functionally interdependent subsystems." (Richard F Ericson, "Organizational cybernetics and human values", 1969) 

"Organizationally what is required - and evolving - is systems management." (Peter Drucker, "MANAGEMENT: Tasks, Responsibilities, Practices", 1973)

"The subject of study in systems theory is not a 'physical object', a chemical or social phenomenon, for example, but a 'system': a formal relationship between observed features or attributes. For conceptual reasons, the language used in describing the behavior of systems is that of information processing and goal seeking (decision making control)." (Mihajlo D Mesarovic & Y Takahara, "Foundations for the mathematical theory of general systems", 1975)

"Systems theory looks at the world in terms of the interrelatedness and interdependence of all phenomena, and in this framework an integrated whole whose properties cannot be reduced to those of its parts is called a system. Living organisms, societies, and ecosystems are all systems." (Fritjof Capra, "The Turning Point: Science, Society, and the Turning Culture", 1982)

"The supposition is prevalent the world over that there would be no problems in production or service if only our production workers would do their jobs in the way that they we taught. Pleasant dreams. The workers are handicapped by the system, and the system belongs to the management." (W Edwards Deming, "Out Of The Crisis", 1982)

"A cardinal principle in systems theory is that all parties that have a stake in a system should be represented in its management." (Malcolm Knowles, "The Adult Learner: A Neglected Species", 1984)

"A manager of people needs to understand that all people are different. This is not ranking people. He needs to understand that the performance of anyone is governed largely by the system that he works in, the responsibility of management." (W Edwards Deming, "The New Economics: For Industry, Government, Education", 1993)

"The prevailing style of management must undergo transformation. A system can not understand itself. The transformation requires a view from outside." (W Edwards Deming, "The New Economics: For Industry, Government, Education", 1993)

More quotes on "Systems Theory" at the-web-of-knowledge.blogspot.com. 

🕸Systems Engineering: Entropy (Definitions)

"The Entropy of a system is the mechanical work it can perform without communication of heat, or alteration of its total volume, all transference of heat being performed by reversible engines." (James C Maxwell, "Theory of Heat", 1899)

"Entropy is the measure of randomness." (Lincoln Barnett, "The Universe and Dr. Einstein", 1948)

"Entropy is a measure of the heat energy in a substance that has been lost and is no longer available for work. It is a measure of the deterioration of a system." (William B. Sill & Norman Hoss (Eds.), "Popular Science Encyclopedia of the Sciences", 1963)

"Entropy [...] is the amount of disorder or randomness present in any system." (Lars Skyttner, "General Systems Theory: Ideas and Applications", 2001)

"A measurement of the disorder of a data set." (Glenn J Myatt, "Making Sense of Data: A Practical Guide to Exploratory Data Analysis and Data Mining", 2006)

"[...] entropy is the amount of hidden microscopic information." (Leonard Susskind, "The Black Hole War", 2008)

"A measure of the uncertainty associated with a random variable. Entropy quantifies information in a piece of data." (Radu Mutihac, "Bayesian Neural Networks for Image Restoration" [in "Encyclopedia of Artificial Intelligence", 2009)

"Measurement that can be used in machine learning on a set of data that is to be classified. In this setting it can be defined as the amount of uncertainty or randomness (or noise) in the data. If all data is classified with the same class, the entropy of that set would be 0." (Isak Taksa et al, "Machine Learning Approach to Search Query Classification", 2009)

"A measure of uncertainty associated with the predictable value of information content. The highest information entropy is when the ambiguity or uncertainty of the outcome is the greatest." (Alex Berson & Lawrence Dubov, "Master Data Management and Data Governance", 2010)

"Refers to the inherent unknowability of data to external observers. If a bit is just as likely to be a 1 as a 0 and a user does not know which it is, then the bit contains 1 bit of entropy." (Mark S Merkow & Lakshmikanth Raghavan, "Secure and Resilient Software Development", 2010)

"The measurement of uncertainty in an outcome, or randomness in a system." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"A metric used to evaluate and describe the amount of randomness associated with a random variable."(Wenbing Zhao, "Increasing the Trustworthiness of Online Gaming Applications", 2015)

"Anti-entropy is the process of detecting differences in replicas. From a performance perspective, it is important to detect and resolve inconsistencies with a minimum amount of data exchange." (Dan Sullivan, "NoSQL for Mere Mortals®", 2015)

"Average amount of information contained in a sample drawn from a distribution or data stream. Measure of uncertainty of the source of information." (Anwesha Sengupta et al, "Alertness Monitoring System for Vehicle Drivers using Physiological Signals", 2016)

"In information theory this notion, introduced by Claude Shannon, is used to express unpredictability of information content. For instance, if a data set containing n items was divided into k groups each comprising n i items, then the entropy of such a partition is H = p 1 log( p 1 ) + … + p k log( p k ), where p i = n i / n . In case of two alternative partitions, the mutual information is a measure of the mutual dependence between these partitions." (Slawomir T Wierzchon, "Ensemble Clustering Data Mining and Databases", 2018) [where i is used as index]

"Entropy is a measure of amount of uncertainty or disorder present in the system within the possible probability distribution." ("G Suseela & Y Asnath V Phamila, "Security Framework for Smart Visual Sensor Networks", 2019)

"Lack of order or predictability; gradual decline into disorder." (Adrian Carballal et al, "Approach to Minimize Bias on Aesthetic Image Datasets", 2019)

"It is the quantity which is used to describe the amount of information which must be coded for compression algorithm." (Arockia Sukanya & Kamalanand Krishnamurthy, "Thresholding Techniques for Dental Radiographic Images: A Comparative Study", 2019)

"In the physics - rate of system´s messiness or disorder in a physical system. In the social systems theory - social entropy is a sociological theory that evaluates social behaviors using a method based on the second law of thermodynamics." (Justína Mikulášková et al, "Spiral Management: New Concept of the Social Systems Management", 2020)

🕸Systems Engineering: Cybernetics (Definitions)

"Cybernetics […] combines under one heading the study of what in a human context is sometimes loosely described as thinking and in engineering is known as control and communication. In other words, cybernetics attempts to find the common elements in the functioning of automatic machines and of the human nervous system, and to develop a theory which will cover the entire field of control and communication in machines and in living organisms." (Norbert Wiener, "Cybernetics", 1948)

The 'cybernetics' of Wiener […] is the science of organization of mechanical and electrical components for stability and purposeful actions." (Qian Xuesen, "Engineering Cybernetics", 1954) 

"[Cybernetics is] the art of ensuring the efficacy of action." (Louis Couffignal, 1958)

"Cybernetics is the science of the process of transmission, processing and storage of information." (Sergei Sobolew, Woprosy Psychology, 1958)

"Cybernetics is the general science of communication. But to refer to communication is consciously or otherwise to refer to distinguishable states of information inputs and outputs and /or to information being processed within some relatively isolated system." (Henryk Greniewski, "Cybernetics without Mathematics", 1960)

"Cybernetics is the science or the art of manipulating defensible metaphors; showing how they may be constructed and what can be inferred as a result of their existence." (Gordon Pask, "The Cybernetics of Human Performance and Learning", 1966)

"Cybernetics is concerned with scientific investigation of systemic processes of a highly varied nature, including such phenomena as regulation, information processing, information storage, adaptation, self-organization, self-reproduction, and strategic behavior. Within the general cybernetic approach, the following theoretical fields have developed: systems theory (system), communication theory, game theory, and decision theory." (Fritz B Simon et al, "Language of Family Therapy: A Systemic Vocabulary and Source Book", 1985)

"Cybernetics is the science of effective organization, of control and communication in animals and machines. It is the art of steersmanship, of regulation and stability. The concern here is with function, not construction, in providing regular and reproducible behaviour in the presence of disturbances." (Chris Lucas, "Cybernetics and Stochastic Systems", 1999)

"Cybernetics is the study of systems and processes that interact with themselves and produce themselves from themselves." (Louis Kauffman, 2007)

"Cybernetics is the art of creating equilibrium in a world of possibilities and constraints." (Ernst von Glasersfeld, "Partial Memories: Sketches from an Improbable Life", 2010)

"Cybernetics is the study of systems which can be mapped using loops (or more complicated looping structures) in the network defining the flow of information. Systems of automatic control will of necessity use at least one loop of information flow providing feedback." (Alan Scrivener, "A Curriculum for Cybernetics and Systems Theory", 2012)

Systems Engineering: Chaos Theory (Definitions)

"A scientific approach – research effort which is based on examining behaviors of nonlinear dynamical systems, which are highly sensitive to their initial conditions." (Utku Köse & Ahmet Arslan, "Chaotic Systems and Their Recent Implementations on Improving Intelligent Systems", 2014)

"Study of deterministic behaviours that depend on initial conditions in physical, natural and social sciences." (Ayşe G Gözüm, "Evaluating HRM Functions within the Context of Chaos and Complexity Theory", 2016)

"The mathematical framework for understanding irregular and erratic fluctuations in economic cycles, financial markets, weather, other complex phenomenon, or non-linear systems with many variables." (Kijpokin Kasemsap, "Utilizing Complexity Theory and Complex Adaptive Systems in Global Business", 2016)

"The study of the behavior of dynamical systems that are highly sensitive to initial conditions." (Rohnn B Sanderson, "Understanding Chaos as an Indicator of Economic Stability", 2016)

"The theory that emerged from mathematics and used widely by other disciplines which concentrates on the dynamical systems." (Çağlar Doğru, "Leader-Member Exchange and Transformational Leadership in Chaos and Complexity", 2016)

"A field of study that explains nonlinear or dynamical systems." (Sharon E Norris, "Examining the Strategic Leadership of Organizations Using Metaphor: Brains and Flux-Interconnected and Interlocked", 2017)

"Chaos theory is the branch of mathematics deals with complicated linear dynamic systems." (Anandkumar R &  Kalpana R, "A Review on Chaos-Based Image Encryption Using Fractal Function", 2020)

"Suggests a randomness of understanding around complex patterns. These may be described as dynamic systems that reflect irregularities and is extremely sensitive to negligible fluctuations or moderations in situation." (Caroline M Crawford et al, "Social Learning Through a Participative Storytelling Framework: Rethinking the Essence of Course Engagement", 2021)

"Chaos theory is a branch of mathematics focusing on the study of chaos - dynamical systems whose random states of disorder and irregularities are governed by underlying patterns and deterministic laws that are highly sensitive to initial conditions." (Nima Norouzi, "Criminal Policy, Security, and Justice in the Time of COVID-19", 2022)

🕸Systems Engineering: Complex Systems (Definitions)

"Roughly, by a complex system I mean one made up of a large number of parts that interact in a nonsimple way." (Herbert Simon, "The Architecture of Complexity", Proceedings of the American Philosophical Society Vol. 106 (6), 1962)

"A complex system is one which possesses mathematical images which are not dynamical systems." (Robert Rosen, On complex systems, European Journal of Operational Research Vol. 30 (2), 1987)

"A complex system is a system formed out of many components whose behavior is emergent, that is, the behavior of the system cannot be simply inferred from the behavior of its components." (Yaneer Bar-Yamm, "Dynamics of Complexity", 1997)

"A system may be called complex here if its dimension (order) is too high and its model (if available) is nonlinear, interconnected, and information on the system is uncertain such that classical techniques can not easily handle the problem." (M Jamshidi, Autonomous Control on Complex Systems: Robotic Applications, Current Advances in Mechanical Design and Production VII, 2000)

"A highly coupled system where the outcomes of the system are the result of the interactions that occur between its different components." (David Lyell et al, "Health Systems Simulation", Encyclopedia of Healthcare Information Systems, 2008)

"Network-based systems characterized by feedback-driven flow of information, openness, self-organization, and emergence. (Ani Calinescu & Janet Efstathiou, "Measures of Network Structure", Encyclopedia of Networked and Virtual Organizations, 2008) 

"[a complex system is] a system in which large networks of components with no central control and simple rules of operation give rise to complex collective behavior, sophisticated information processing, and adaptation via learning or evolution." (Melanie Mitchell, "Complexity: A Guided Tour", 2009)

"Systems made of several interconnected simple parts which altogether exhibit a high degree of complexity from each emerges a higher order behaviour." (Radu Mutihac, "Mathematical Modeling of Artificial Neural Networks", Encyclopedia of Artificial Intelligence, 2009)

"CS [complex system] is a system composed of many heterogeneous agents, which are nonlinearly interconnected, while the final emergence of the system is completely different than the individual element`s performance." (Shahrooz V Manesha & Massimo Tadi, "Sustainable urban morphology emergence via complex adaptive system analysis: sustainable design in existing contex", Procedia Engineering 21, 2011)

"A system that exhibits a mutual interdependency of components and for which a change in the input parameter(s) can result in a non-proportional large or small change of the system output." (Alexander Kolker, Management Science for Healthcare Applications, Encyclopedia of Business Analytics and Optimization, 2014) 

"A system whose intricacy impedes the forecasting of its behaviour." (Valentina M Ghinea, "Modelling and Simulation of the Need for Harmonizing the European Higher Education Systems", Handbook of Research on Trends in European Higher Education Convergence, 2014)

"A system which is usually composed of large number of possibly heterogeneous interacting agents, which are seen to exhibit emergent behavior." (Stephen E Glavin & Abhijit Sengupta, "Modelling of Consumer Goods Markets: An Agent-Based Computational Approach", Handbook of Research on Managing and Influencing Consumer Behavior, 2015)

"Complex systems are networks made of a number of components that interact with each other, typically in a nonlinear fashion. Complex systems may arise and evolve through self-organization, such that they are neither completely regular nor completely random, permitting the development of emergent behavior at macroscopic scales." (Hiroki Sayama, "Introduction to the Modeling and Analysis of Complex Systems", 2015)

"The occurrence of new phenomena generated unpredictably by the interaction of simple rules and individual mechanisms that are in constant flux and interaction. Emergence suggests something novel is perpetually emerging at a systems/global level as the world and environment constantly shifts and changes at a mechanistic/local level." (Kathy Sanford & Tim Hopper, "Digital Media in the Classroom: Emergent Perspectives for 21st Century Learners", Handbook of Research on Digital Media and Creative Technologies, 2015)

"A system characterized by the number of the elements that constitute it, and by the nature of the interactions between these elements." (Manuela Piscitelli, "Application of Complexity Theory in Representation of the City", Handbook of Research on Chaos and Complexity Theory in the Social Sciences, 2016)

"A complex system means a system whose perceived complicated behaviors can be attributed to one or more of the following characteristics: large number of element, large number of relationships among elements, non-linear and discontinuous relationship, and uncertain characteristics of elements." (Chunfang Zhou, "Fostering Creative Problem Solvers in Higher Education: A Response to Complexity of Societies", Handbook of Research on Creative Problem-Solving Skill Development in Higher Education, 2017)

"System made up of many interconnected elements on various levels; interactions on lower levels give rise to events on higher levels." (Naomi Thompson & Joshua Danish, "Designing BioSim: Playfully Encouraging Systems Thinking in Young Children", Handbook of Research on Serious Games for Educational Applications, 2017)

🕸Systems Engineering: Emergence (Definitions)

"Emergence is the phenomenon of properties, capabilities and behaviours evident in the whole system that are not exclusively ascribable to any of its parts." (Derek Hitchins, "Advanced Systems Thinking, Engineering and Management", 2003)

"The process of complex pattern formation from simpler rules; emergent properties are neither properties had by any parts of the system taken in isolation nor a resultant of a mere summation of properties of parts of the system." (Ani Calinescu & Janet Efstathiou, "Measures of Network Structure", Encyclopedia of Networked and Virtual Organizations, 2008) 

"A process where phenomena at a certain level arise from interactions at lower levels. The term is sometimes used to denote a property of a system not contained in any one of its parts." (Max Lungarella & Gabriel Gómez, "Developmental Robotics", Encyclopedia of Artificial Intelligence, 2009)

"Emergence is defined as the occurrence of new processes operating at a higher level of abstraction then is the level at which the local rules operate." (Jirí Kroc & Peter M A Sloot, "Complex Systems Modeling by Cellular Automata", Encyclopedia of Artificial Intelligence, 2009)

"Phenomenon through which complex systems and patterns emerge from multiple simple and local interactions. Emergence is central to the theory of complex systems." (Marielba Zacarias et al, "Modeling Human Resources in the Emergent Organization", Handbook of Research on E-Transformation and Human Resources Management Technologies, 2009)

"Refers to new unexpected behaviors and patterns that arise out of a multiplicity of relatively simple interactions. An emergent behavior can appear when a number of simple entities (agents) operate in an environment while forming more complex behaviors as a community."  (Andrew Kuznetsov, "Synthetic Biology as a Proof of Systems Biology", Handbook of Research on Systems Biology Applications in Medicine, 2009)

"The process of coherent patterns of behavior arising from the self-organizing aspects of complex systems." (Brian L Heath & Raymond R. Hill, "Agent-Based Modeling: A Historical Perspective and a Review of Validation and Verification Efforts", Handbook of Research on Discrete Event Simulation Environments: Technologies and Applications, 2010)

"The notion of emergence is used in a variety of disciplines such as evolutionary biology, the philosophy of mind and sociology, as well as in computational and complexity theory. It is associated with non-reductive naturalism, which claims that a hierarchy of levels of reality exist. While the emergent level is constituted by the underlying level, it is nevertheless autonomous from the constituting level. As a naturalistic theory, it excludes non-natural explanations such as vitalistic forces or entelechy. As non-reductive naturalism, emergence theory claims that higher-level entities cannot be explained by lower-level entities." (Martin Neumann, "An Epistemological Gap in Simulation Technologies and the Science of Society", 2011)

"Emergence is a nontrivial relationship between the properties of a system at microscopic and macroscopic scales. Macroscopic properties are called emergent when it is hard to explain them simply from microscopic properties." (Hiroki Sayama, "Introduction to the Modeling and Analysis of Complex Systems", 2015)

"Process whereby global patterns arise through interactions between local and simple entities that themselves do not exhibit such patterns." (Carlos M Fernandes & Ivo D de Sousa, "Digital Swarms: Social Interaction and Emergent Phenomena in Personal Communications Networks, 2017)

"The insurgence, in a group or collective of individuals, of properties that are not shared by any single individual. It is the 'more' in the expression 'the whole is more than just the sum of its constituent parts'." (Alessio Erioli, "Anexact Paths: Computation, Continuity, and Tectonics in the Design Process", Handbook of Research on Form and Morphogenesis in Modern Architectural Contexts, 2018)

"Unexpected phenomena appearing (and often having a regularity or pattern) from a collection of apparently unrelated elements and where the elements themselves do not have the characteristics of the phenomena and that phenomena itself is not contained deductively within the elements." (Jeremy Horne, "Visualizing Big Data From a Philosophical Perspective", Handbook of Research on Big Data Storage and Visualization Techniques, 2018)

"A feature in a complex system that is generated through the dynamic interactions between the parts of a system at one level, and is realized at the next level of organization without intentionality or causality." (A Faye Bres, "Integral Post-Analysis of Design-Based Research of an Organizational Learning Process for Strategic Renewal of Environmental Management", Integral Theory and Transdisciplinary Action Research in Education, 2019)

"Feature of complex systems, meaning that the interactions between system’s components lead to unexpected behavioral properties, resulting from system’s self-organizational processes." (Francesca Costanza, "Managing Patients' Organizations to Improve Healthcare: Emerging Research and Opportunities", 2020)

"The capacity for a system to produce outputs which were unexpected by the original designers." (Kenneth Chen, "The Fallacies of MDA for Novice Designers: Overusing Mechanics and Underusing Aesthetics", Interactivity and the Future of the Human-Computer Interface, 2020)

🕸Systems Engineering: Self-Organization (Definitions)

"Self-organization can be defined as the spontaneous creation of a globally coherent pattern out of local interactions." (Francis Heylighen, "The Science Of Self-Organization And Adaptivity", 1970)

"Self-organization refers to the spontaneous formation of patterns and pattern change in open, nonequilibrium systems." (J A Scott Kelso, "Dynamic Patterns : The Self-organization of Brain and Behavior", 1995)

"[…] self-organization is the spontaneous emergence of new structures and new forms of behavior in open systems far from equilibrium, characterized by internal feedback loops and described mathematically by nonlinear equations." (Fritjof  Capra, "The web of life: a new scientific understanding of living  systems", 1996)

"A system described as self-organizing is one in which elements interact in order to achieve dynamically a global function or behavior." (Carlos Gershenson, "A general methodology for designing self-organizing systems", 2006)

"In engineering, a self-organizing system would be one in which elements are designed to dynamically and autonomously solve a problem or perform a function at the system level." (Carlos Gershenson, "Design and Control of Self-organizing Systems", 2007)

"The components of a system make local decisions that have a coherent, organizing impact on the system as a whole. Therefore, the system displays organization without any external organizing principle being applied." (Ani Calinescu & Janet Efstathiou, "Measures of Network Structure", Encyclopedia of Networked and Virtual Organizations, 2008) 

"The process by which a system chooses way at a bifurcation point as a result of both individual variability and communication between individuals." (Tomas Backström & Marianne Döös, "Relatonics as a Key Concept for Networked Organizations", Encyclopedia of Networked and Virtual Organizations, 2008)

"A characteristic of complex and adaptive systems that display emergent behavior. A structure that self-organizes and gets its smarts from below; agents residing on a scale start producing behavior that lies one scale above them (e.g., ants create colonies, learners create learning communities)." (Daniel Burgos et al, Design Guidelines for Collaboration and Participation with Examples from the LN4LD, Handbook of Research on Learning Design and Learning Objects, 2009)

"It is a process in which the internal organization of a system, normally an open system, increases in complexity without being guided or managed by an outside source. Self-organizing systems typically exhibit emergent behavior." (Vineet R Khare & Frank Z Wang, "Bio-Inspired Grid Resource Management", Handbook of Research on Grid Technologies and Utility Computing, 2009)

"Self-organization is a process typically occurring within complex systems where a system is continuously fed by energy, which is transformed into a new system state or operational mode by a dissipation of energy and/or information." (Jirí Kroc & Peter M A Sloot, "Complex Systems Modeling by Cellular Automata", Encyclopedia of Artificial Intelligence, 2009)

"The ability of a system to arrange and organize itself spontaneously under appropriate circumstances in a purposeful (non-random) manner without any help of external agencies." (Ali Diab & Andreas Mitschele-Thiel, "Self-Organization Activities in LTE-Advanced Networks", Handbook of Research on Progressive Trends in Wireless Communications and Networking, 2014)

"Self-organization is a dynamical process by which a system spontaneously forms nontrivial macroscopic structures and/or behaviors over time." (Hiroki Sayama, "Introduction to the Modeling and Analysis of Complex Systems", 2015)

"Refers to how a system of agents organizes itself into a higher order and emerges from a set of simple rules in an interconnected network." (Wassim J Aloulou, "Understanding Entrepreneurship through Chaos and Complexity Perspectives", Handbook of Research on Chaos and Complexity Theory in the Social Sciences, 2016)

"The ability of a system to spontaneously arrange its components in a purposeful (non-random) manner, under appropriate conditions but without the help of an external agency." (Kijpokin Kasemsap, "Utilizing Complexity Theory and Complex Adaptive Systems in Global Business", Handbook of Research on Chaos and Complexity Theory in the Social Sciences, 2016)

"A process where a form of global order in a system (emergence of patterns at the global scale) arises by means and as a consequence of local interactions." (Alessio Erioli, "Anexact Paths: Computation, Continuity, and Tectonics in the Design Process", Handbook of Research on Form and Morphogenesis in Modern Architectural Contexts, 2018)

"This is a phenomenon, where elements self-organize under the influence of stimuli. In an organisation for self-organisation three elements are crucial: the purpose, values (principles) and the motivation of employees that is results from their responsibility." (Edyta Abramek, "Training Company Self-Organization", Handbook of Research on Autopoiesis and Self-Sustaining Processes for Organizational Success, 2021)

🕸Systems Engineering: System (Definitions)

"A system is an imaginary machine invented to connect together in the fancy those different movements and effects which are already in reality performed." (Adam Smith, "The Wealth of Nations", 1776)

"A system is a methodical arrangement of propositions and proofs; and without such arrangement, no distinct and certain knowlege of any subject can be obtained." (Johann G Burckhardt, 1797) 

"A system is a set of objects compromising all that stands to one another in a group of connected relations." (Charles S Peirce, "Cambridge Lectures on Reasoning and the Logic of Things: Detached Ideas on Vitally Important Topics", 1898)

"A system is a whole which is composed of various parts. But it is not the same thing as an aggregate or heap. In an aggregate or heap, no essential relation exists between the units of which it is composed. In a heap of grain, or pile of stones, one may take away part without the other part being at all affected thereby. But in a system, each part has a fixed and necessary relation to the whole and to all the other parts." (James E Creighton, "An Introductory Logic"‎, 1909)

"A system is any portion of the universe set aside for certain specified purposes. For our concern, a system is set aside from the universe in a manner that will enable this system to be built without having to consider the total universe. Therefore, the system is set aside from the universe by its inputs and outputs - its boundaries." (Kay Inaba et al, "A rational method for applying behavioral technology to man-machine system design", 1956)

"A System is a set of elements in interaction." (Ludwig von Bertalanffy, "General System Theory", 1968)

"A system is a set of two or more elements that satisfies the following three conditions. (1) The behavior of each element has an effect on the behavior of the whole. (2) The behavior of the elements and their effects on the whole are interdependent. the way each element behaves and the way it affects the whole depends on how at least one other element behaves. (3) However subgroups of the elements are formed, each has an effect on the behavior of the whole and none has an independent effect on it." (Russell L Ackoff, "Creating the Corporate Future", 1981) 

"A system is a network of interdependent components that work together to try to accomplish the aim of the system.” (William E Deming, "The New Economics for Industry, Government, Education”, 1993)

"In the most abstract sense, a system is a set of objects together with relationships among the objects. Such a definition implies that a system has properties, functions, and dynamics distinct from its constituent objects and relationships." (Tom R. Burns, "System Theories", 2006) 

"A complex entity that comprises a set of components, along with their properties, relationships and processes, which is described by an equivalent mathematical model." (Evangelos C Papakitsos et al, "The Challenges of Work-Based Learning via Systemic Modelling in the European Union", 2020)

"A group of elements or parts that are organized and interrelated in a pattern of structures that design a specific set of behaviors, often classified as its 'function' or 'purpose'." (Tatiana C Valencia & Stephanie J Valencia, "Cultivating Flow and Happiness in Children", 2020)

"Any notion or physical entity, comprising of mutually interlinked and interacting parts; a set of elements and relationships between them capable of realizing specified objectives; set of elements with specified structure and enabling logically ordered whole, arranged set of statements, views." (Jaroslaw Zelinski, "Synthesis of MOF, MDA, PIM, MVC, and BCE Notations and Patterns", 2020)

🕸Systems Engineering: Systems Theory (Definitions)

"Systems theory pursues the scientific exploration and understanding of systems that exist in the various realms of experience, in order to arrive at a general theory of systems: an organized expressing of sets of interrelated concepts and principles that apply to all systems." (Béla H Bánáthy, "Systems Design of Education", 1991)

"Systems theory is an interdisciplinary field of science concerned with the nature of complex systems, be they physical or natural or purely mathematical." (Thomas B Sheridan, The System Perspective on Human Factors in Aviation, 2010) 

"Systems theory is the interdisciplinary study of systems in general, with the goal of elucidating principles that can be applied to all types of systems at all nesting levels in all fields of research. The term does not yet have a well-established, precise meaning, but systems theory can reasonably be considered a specialization of systems thinking; alternatively as a goal output of systems science and systems engineering, with an emphasis on generality useful across a broad range of systems (versus the particular models of individual fields)." (Gabriela Walker & Elizabeth Pattison, "Using Bronfenbrenner's Ecological Framework to Design Support Systems for Education and Special Education: Learning About Thought Systems", 2016)

"The assumption that quality of a part of a system can only be understood in its relationship to the whole and investigating the parts in isolation cannot explain their combined effect on the whole system." (Margaret S Suubi, "Education for Sustainable Development (ESD) in Higher Education", 2019) 

"Framework of describing how smaller, multiple units and components work together to create a larger system that is designed to carry out a particular function or meet a certain goal." (RaMonda Horton, "Systems-Based Approaches to Speech-Language Pathology Service Delivery for School Age Children", 2020)

"Is an interdisciplinary study of systems that takes a holistic approach to analysis that focuses on the elements within a system, how they interrelate, how they work over time and within the context of larger systems (e.g., natural or man-made)." (Tatiana C Valencia & Stephanie J Valencia, "Cultivating Flow and Happiness in Children", 2020)

"Systems theory is an interdisciplinary theory about the nature of complex systems in nature, society, and science. It is a framework by which one can use to study, investigate and describe any group of objects that work in collaboration towards a common purpose/goal."

(Cheryl M Cordeiro et al, "Culture From a Value Systems Perspective", 2020)

"The domain of systems inquiry that explores the principles and the description models of the abstract organization of phenomena, in an interdisciplinary manner and independently of their nature (natural or social systems) or scale of existence." (Evangelos C Papakitsos et al, "The Challenges of Work-Based Learning via Systemic Modelling in the European Union", 2020)

"Theory that holds that systems in nature are holistic, interconnected and interdependent. If a change occurs in one part of a system, other parts of the system are affected as well." (Joe Monaco & Edward W Schneider, "Building Performance Systems That Last", 2020)

🚧Project Management: Project Planning (Just the Quotes)

"Planning starts usually with something like a general idea. For one reason or another it seems desirable to reach a certain objective, and how to reach it is frequently not too clear. The first step then is to examine the idea carefully in the light of the means available. Frequently more fact-finding about the situation is required. If this first period of planning is successful, two items emerge: namely, an 'over-all plan' of how to reach the objective and secondly, a decision in regard to the first step of action. Usually this planning has also somewhat modified the original idea. The next period is devoted to executing the first step of the original plan." (Kurt Lewin, "Action research and minority problems", 1946)

"Every company has beloved projects on which if prices had held up, if the contractors had finished on time (or finished at all), if the plans hadn't been altered, if the thing had actually worked, the planned return would have been earned. But since some or all of these calamities [things that don't go as expected] usually happen, any manager who neglects to allow for them is not planning - merely thinking wishfully. Desire for the project has, as usual, overtaken desire for profit." (Ernest Dale, "Planning and developing the company organization structure", 1952)

"Project management is the process by which it is assured that the objective is achieved and resources are not wasted. Planning is one of the two parts of project management. Control is the other. [...] Each project must first be planned in detail. Control is involved with comparing actual progress with the plan and taking corrective action when the two do not correspond. Without the plan, true control is not possible; the need for corrective action, its nature, extent, and urgency cannot he accurately determined." (Robert D Carlsen & James A Lewis, "The Systems Analysis Workbook: A complete guide to project implementation and control", 1973)

"Since software construction is inherently a systems effort - an exercise in complex interrelationships - communication effort is great, and it quickly dominates the decrease in individual task time brought about by partitioning [increasing the workers]. Adding more people then lengthens, not shortens, the schedule." (Frederick Brook, "The Mythical Man-Month", 1975)

"Because one has to be an optimist to begin an ambitious project, it is not surprising that underestimation of completion time is the norm." (Fernando J Corbató, "On Building Systems That Will Fail", 1991)

"If we decide to plan not to lose, we take a defensive posture in which we expend huge amounts of effort trying to prevent and track errors. This will lead us to a very heavyweight planning process in which we try to plan everything up front in a much detail as possible. Such a process will have many review steps, sign-offs, authorizations, and phase gates. Such a planning process is highly adept at making sure that blame can be assigned when something fails; but takes no direct steps towards making sure that the right system is delivered at a reasonable cost." (Kent Beck & Martin Fowler, "Planning Extreme Programming", 2000)

"One of the purposes of planning is we always want to work on the most valuable thing possible at any given time. We can’t pick features at random and expect them to be most valuable. We have to begin development by taking a quick look at everything that might be valuable, putting all our cards on the table. At the beginning of each iteration the business (remember the balance of power) will pick the most valuable features for the next iteration." (Kent Beck & Martin Fowler, "Planning Extreme Programming", 2000)

"Planning is not about predicting the future. When you make a plan for developing a piece of software, development is not going to go like that. Not ever. Your customers wouldn’t even be happy if it did, because by the time software gets there, the customers don’t want what was planned, they want something different." (Kent Beck & Martin Fowler, "Planning Extreme Programming", 2000)

"Projects sometimes fail long before they deliver anything. At some point they may be determined to be too expensive to continue. Or perhaps they took too long to develop and the business need evaporated. Or perhaps the requirements change so often that the developers can never finish one thing without having to stop and start all over on something new. Certainly these are planning failures." (Kent Beck & Martin Fowler, "Planning Extreme Programming", 2000)

"There are two ways to approach prevention of these planning failures. We can plan not to lose, or we can plan to win. The two are not identical. Planning not to lose is defensive; while planning to win is aggressive. [...] the problem that planning is supposed to solve is simply, to build the right system at the right cost. If we take a defensive posture by planning not to lose, we will be able to hold people accountable for any failures; but at an enormous cost. If we take an aggressive posture and plan to win, we will be unafraid to make errors, and will continuously correct them to meet our goals." (Kent Beck & Martin Fowler, "Planning Extreme Programming", 2000)

"We plan because: We need to ensure that we are always working on the most important thing we need to do. We need to coordinate with other people. When unexpected events occur we need to understand the consequences for the first two." (Kent Beck & Martin Fowler, "Planning Extreme Programming", 2000)

"When we plan to win we take direct steps to ensure that we are building the right system at the best possible cost. Every action we take goes towards that end. Instead of trying to plan everything up front, we plan just the next few steps; and then allow customer feedback to correct our trajectory. In this way, we get off the mark quickly, and then continuously correct our direction. Errors are unimportant because they will be corrected quickly." (Kent Beck & Martin Fowler, "Planning Extreme Programming", 2000)

"If you have no plan, you cannot have control, by definition, because it is your plan that tells where you are supposed to be in the first place. Further, if you don’t know where you are, you can’t have control. This comes from your information system. Most organizations have difficulties with both of these." (James P Lewis, "Project Planning, Scheduling, and Control" 3rd Ed., 2001)

"No project can succeed when the team members have no commitment to the plan, so the first rule of project planning is that the people who must do the work should help plan that part of the project. You will not only gain their commitment to the plan, but also most likely cover all of the important issues that you may individually have forgotten."(James P Lewis, "Project Planning, Scheduling, and Control" 3rd Ed., 2001)

"The big fallacy in our assumptions is that the world will stand still while we execute our project plan." (James P Lewis, "Project Planning, Scheduling, and Control" 3rd Ed., 2001)

"Project planning is the key to effective project management. Detailed and accurate planning of a project produces the managerial information that is the basis of project justification (costs, benefits, strategic impact, etc.) and the defining of the business drivers (scope, objectives) that form the context for the technical solution. In addition, project planning also produces the project schedules and resource allocations that are the framework for the other project management processes: tracking, reporting, and review." (Rob Thomsett, "Radical Project Management", 2002)

"If you've been in the software business for any time at all, you know that there are certain common problems that plague one project after another. Missed schedules and creeping requirements are not things that just happen to you once and then go away, never to appear again. Rather, they are part of the territory. We all know that. What's odd is that we don't plan our projects as if we knew it. Instead, we plan as if our past problems are locked in the past and will never rear their ugly heads again. Of course, you know that isn't a reasonable expectation." (Tom DeMarco & Timothy Lister, "Waltzing with Bears: Managing Risk on Software Projects", 2003)

"The pathology of setting a deadline to the earliest articulable date essentially guarantees that the schedule will be missed." (Tom DeMarco & Timothy Lister, "Waltzing with Bears: Managing Risk on Software Projects", 2003)

"Ending up somewhere entirely different from where you expected to go is the norm in this world. Software projects are prime illustrations of the law of unintended consequences, and their innovations and breakthroughs are more often side effects than planned outcomes." (Scott Rosenberg, "Dreaming in Code", 2007)

"[…] in software development, as in all things, plans get dodgier the farther into the future one looks. Any developer who has been around the block will admit that the cavalcade of methodologies over three decades of software history has left the field richer and given programmers useful new tools and ways of thinking about their work. But finding a developer or team that actually subscribes to a particular methodology isn’t easy." (Scott Rosenberg, "Dreaming in Code", 2007)

"The picture of digital progress that so many ardent boosters paint ignores the painful record of actual programmers’ epic struggles to bend brittle code into functional shape. That record is of one disaster after another, marking the field’s historical time line like craters. Anyone contemplating the start of a big software development project today has to contend with this unfathomably discouraging burden of experience. It mocks any newcomer with ambitious plans, as if to say, What makes you think you’re any different?" (Scott Rosenberg, "Dreaming in Code", 2007)

"Users may be annoyed by bugs, and software developers may be disappointed by their inability to perfect their work, and managers may be frustrated by the unreliability of their plans. But in the end, none of that matters as much as the simple fact that software does not work the way we think, and until it does, it is not worth trying to perfect." (Scott Rosenberg, "Dreaming in Code", 2007)

"And even if we make good plans based on the best information available at the time and people do exactly what we plan, the effects of our actions may not be the ones we wanted because the environment is nonlinear and hence is fundamentally unpredictable. As time passes the situation will change, chance events will occur, other agents such as customers or competitors will take actions of their own, and we will find that what we do is only one factor among several which create a new situation." (Stephen Bungay, "The Art of Action: How Leaders Close the Gaps between Plans, Actions, and Results", 2010)

"A project plan is a prediction. It predicts that a team of N people will complete X amount of work by Y date." (Sriram Narayan, "Agile IT Organization Design: For Digital Transformation and Continuous Delivery", 2015)

"Development is a design process. Design processes are generally evaluated by the value they deliver rather than a conformance to plan. Therefore, it makes sense to move away from plan-driven projects and toward value-driven projects. […] The realization that the source code is part of the design, not the product, fundamentally rewires our understanding of software." (Sriram Narayan, "Agile IT Organization Design: For Digital Transformation and Continuous Delivery", 2015)

"The planning fallacy is the systematic tendency for project plans and budgets to undershoot. […] The reasons for the planning fallacy are partly psychological, partly cultural, and partly to do with our limited ability to think probabilistically." (Paul Gibbons, "The Science of Successful Organizational Change",  2015)

"An effort estimate is not complete without including its assumptions. Estimate assumptions include any and all underlying factors the estimate relies upon. Assumptions are especially important in more rigid estimation environments, but they are a good practice even where expectations are more flexible. Explicitly listing all assumptions helps to remove ambiguity and avoid misunderstandings during project delivery." (Morgan Evans, "Engineering Manager's Handbook", 2023)

"Plans allow us to think through objectives beforehand in the hope of being prepared for delivery. Plans are useful when they preempt conflict, direct efforts in harmony, and align expectations. Plans are not useful when they waste valuable build time or provide a false sense of security, for example, by missing unknown unknowns." (Morgan Evans, "Engineering Manager's Handbook", 2023)

🚧Project Management: Risk (Just the Quotes)

"But the greater the primary risk, the safer and more careful your secondary assumptions must be. A project is only as sound as its weakest assumption, or its largest uncertainty." (Robert Heller, "The Naked Manager: Games Executives Play", 1972)

"Today, most project management practitioners focus on planning failure. If this aspect of the project can be compressed, or even eliminated, then the magnitude of the actual failure, should it occur, would be diminished. A good project management methodology helps to reduce planning failure. Today, we believe that planning failure, when it occurs, is due in large part to the project manager’s inability to perform effective risk management." (Harold Kerzner, "Strategic Planning for Project Management using a Project Management Maturity Model", 2001)

"Risks and benefits always go hand in hand. The reason that a project is full of risk is that it leads you into uncharted waters. It stretches your capability, which means that if you pull it off successfully, it's going to drive your competition batty. The ultimate coup is to stretch your own capability to a point beyond the competition's ability to respond. This is what gives you competitive advantage and helps you build a distinct brand in the market." (Tom DeMarco & Timothy Lister, "Waltzing with Bears: Managing Risk on Software Projects", 2003)

"The business of believing only what you have a right to believe is called risk management." (Tom DeMarco & Timothy Lister, "Waltzing with Bears: Managing Risk on Software Projects", 2003)

"In project management there are two levels of opportunities and risks. Because a project is the pursuit of an opportunity, the first category, the macro opportunity, is the project opportunity itself. The approach to achieving the project opportunity and the mitigation of associated project-level risks are structured into the strategy and tactics of the project cycle, the selected decision gates, the teaming arrangements, key personnel selected, and so on. The second level encompasses the tactical opportunities and risks within the project that become apparent at lower levels of decomposition and as project cycle phases are planned and executed. This can include emerging, unproven technology; incremental and evolutionary methods that promise high returns; and the temptation to circumvent proven practices in order to deliver better, faster, and cheaper." (Kevin Forsberg et al, "Visualizing Project Management: Models and frameworks for mastering complex systems" 3rd Ed., 2005)

"Opportunities and risks are endemic to the project environment. However well planned a project may be, there will always be residual project risk." (Kevin Forsberg et al, "Visualizing Project Management: Models and frameworks for mastering complex systems" 3rd Ed., 2005)

"When we pursue opportunity, we normally incur risk. The opportunity to experience the thrill of an exciting sport like hang gliding or scuba diving brings with it the attendant risks. Many people instinctively make the trade that the thrill is worth the risks. Others decline." (Kevin Forsberg et al, "Visualizing Project Management: Models and frameworks for mastering complex systems" 3rd Ed., 2005)

"For most projects there will be many sources of risk. Assumptions that seem quite reasonable at the start of a project may be proven otherwise if and when conditions in internal or external environments change during the project duration." (Roger Jones & Neil Murra, "Change, Strategy and Projects at Work", 2008)

"Routine tasks are, by their nature, familiar to us. The outcomes of performing routine tasks are therefore usually highly predictable. Project work by contrast includes elements of risk and uncertainty associated with the uniqueness and unfamiliarity of some of the work or the context in which it is carried out. Murphy’s Law expresses a ‘tongue-in-cheek’ but fallacious certainty of things going wrong, if it is possible for them to go wrong." (Roger Jones & Neil Murra, "Change, Strategy and Projects at Work", 2008)

"Whilst culture can help create a sense of belonging and shared destiny, it can also prove to be an obstacle to change especially where the existing culture is risk averse or if the change strategy is perceived by some to challenge prevailing group values. Where radical change is proposed, the achievement of cultural change may actually be a major objective of the proposed change." (Roger Jones & Neil Murra, "Change, Strategy and Projects at Work", 2008)

"A project is usually considered a failure if it is late, is over budget, or does not meet the customer’s expectations. Without the control that project management provides, a project is more likely to have problems with one of these areas. A problem with only one constraint (scope, schedule, cost, resources, quality, and risk) can jeopardize the entire project." (Sandra F Rowe, "Project Management for Small Projects" 3rd Ed., 2020)

🚧Project Management: Laws (Just the Quotes)

"Nothing will ever be attempted if all possible objections must first be overcome." (Samuel Johnson, 1759)

"Remember, if you fail to prepare you are preparing to fail." (H K Williams, 1919)

"If we fail to prepare we prepare to fail." (James H Hope, 1929)

"In anything at all, perfection is finally attained not when there is no longer anything to add, but when there is no longer anything to take away [...]" (Antoine de Saint Exupéry, "Wind, Sand and Stars", 1939) 

"Work expands so as to fill the time available for its completion." (C Northcote Parkinson, "Parkinson’s Law", 1957) 

"Adding manpower to a late software project makes it later." (Fred Brooks, "The Mythical Man-Month", 1975)

"By failing to plan, you will free very little, if any, time, and by failing to plan you will almost certainly fail […] Exactly because we lack time to plan, we should take time to plan." (Alan Lakein, "How to get control of your time and your life", 1974) 

"Program advocates like to keep bad news covered up until they have spent so much money they can advance the sunk-cost argument; that it's too late to cancel the program because we've spent too much already." (James P Stevenson, "The Pentagon Paradox: The development of the F-18 Hornet", 1993)

Graham's Law: "If they know nothing of what you are doing, they suspect you are doing nothing." (Robert J Graham et al, "The Complete Idiot's Guide to Project Management", 2007) 

O'Brochta's Law: "Project management is about applying common sense with uncommon discipline." (Michael O'Brochta, "Great Project Managers", 2008) 

"No project should be allowed to proceed without clear specification and acceptance  criteria, that are understood by all participants." (Tony Martyr, "Why Projects Fail", 2018)

Augustine's Law: "A bad idea executed to perfection is still a bad idea." (Norman R Augustine)

Cohn's Law: "The more time you spend in reporting on what you are doing, the less time you have to do anything. Stability is achieved when you spend all your time doing nothing but reporting on the nothing you are doing."

Dobbins’ Law: "When in doubt, use a bigger hammer."

Fitzgerald's Law: "There are two states to any large project: Too early to tell and too late to stop." (Ernest Fitzgerald)

Hoggarth's Law: "Attempts to get answers early in a project fail as there are many more wrong questions than right ones. Activity during the early stages should be dedicated to finding the correct questions. Once the correct questions have been identified correct answers will naturally fall out of subsequent work without grief or excitement and there will be understanding of what the project is meant to achieve."

Kinser's Law: "About the time you finish doing something, you know enough to start." (James C Kinser) 

Wolf ’s Law of Management: "The tasks to do immediately are the minor ones; otherwise, you’ll forget them. The major ones are often better to defer. They usually need more time for reflection. Besides, if you forget them, they’ll remind you."

Operations Management: Operations Research (Just the Quotes)

"No science has ever been born on a specific day. Each science emerges out of a convergence of an increased interest in some class of problems and the development of scientific methods, techniques, and tools which are adequate to solve these problems. Operations Research (O. R.) is no exception. Its roots are as old as science and the management function." (C West Churchman et al., "Introduction to Operations Research", 1957)

"An objective of O.R. as it emerged from this evolution of industrial organization, is to provide managers of the organizations with a scientific basis for solving problems involving the interaction of the components of the organization in the best interest of the organization as a whole. A decision which is best for the organization as a whole is called optimum decision." (C West Churchman et al, "Introduction to Operations Research", 1957) 

"The systems approach to problems does not mean that the most generally formulated problem must be solved in one research project. However desirable this may be, it is seldom possible to realize it in practice. In practice, parts of the total problem are usually solved in sequence. In many cases the total problem cannot be formulated in advance but the solution of one phase of it helps define the next phase. For example, a production control project may require determination of the most economic production quantities of different items. Once these are found it may turn out that these quantities cannot be produced on the available equipment in the available time. This, then, gives rise to a new problem whose solution will affect the solution obtained in the first phase." (C West Churchman et al, "Introduction to Operations Research", 1957) 

"The concern of OR with finding an optimum decision, policy, or design is one of its essential characteristics. It does not seek merely to define a better solution to a problem than the one in use; it seeks the best solution... [It] can be characterized as the application of scientific methods, techniques, and tools to problems involving the operations of systems so as to provide those in control of the operations with optimum solutions to the problems." (C West Churchman et al, "Introduction to Operations Research", 1957) 

"Operational research is the application of methods of the research scientist to various rather complex practical operations." (John F T Hassell, "The Scientific Approach", 1965) 

"Operations research (OR) is the securing of improvement in social systems by means of scientific method." (C West Churchman, "Operations research as a profession", 1970)

"Decision theory, as it has grown up in recent years, is a formalization of the problems involved in making optimal choices. In a certain sense - a very abstract sense, to be sure - it incorporates among others operations research, theoretical economics, and wide areas of statistics, among others." (Kenneth Arrow, "The Economics of Information", 1984) 

"The lag between knowing the facts and knowing the system which generates the facts can be considerable. […] Similarly there is a lag in passing from the stage in which sets of empirical observations constitute exciting discoveries, to the stage of insight into underlying mechanism, in every field of management today. In controlling the economy and diplomacy and society at large, in controlling business and industry and commerce, we have collected facts and perhaps identified systems. But we have barely begun to explain their underlying mechanism. This is what operational research is for." (Stanford Beer, "Decision and Control", 1994)