Chreod
Encyclopedia
Chreod, is a portmanteau term coined by 20th century biologist Conrad Hal Waddington
that combines the Greek
word for "determined" or "necessary" and the word for "pathway." The term was used along with homeorhesis
, which describes a system that returns to a steady trajectory in contrast to homeostasis
which describes a system which returns to a steady state. Architectural Theorist Sanford Kwinter
described the concept of the cherod as "the most important concept of the 20th century."
The word "chreod" also closely describes paths of decision within what Christopher Alexander
has called, configuration space
, his term for what he notes that Stuart Kaufmann calls "fitness landscape." Configuration space is a conceptual landscape which contains all possible outcomes and points of decision within the design of a structure or the growth of an organism or system. Because so very few of the possible outcomes will be good ones, paths to the infinitesimally rare possible and good solutions must be followed to get good results. These paths or, "chreods" appear to be followed automatically in the biological world. (see the cited Kwinter excerpt) By Alexander's theory, because conscious human design decisions do not need to follow these chreods, conscious human design can lead to mixed results. Therefore, he proposes that discovering ways to allow architecture to follow these paths is the best way to get good results in the built environment. Alexander sees his theories of "The Fundamental Process," "structure preserving transformations" and "15 fundamental properties" which he outlines in his four volume work, The Nature of Order
as instrumentally shaping paths through configuration space.
Conrad Hal Waddington
Conrad Hal Waddington CBE FRS FRSE was a developmental biologist, paleontologist, geneticist, embryologist and philosopher who laid the foundations for systems biology...
that combines the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
word for "determined" or "necessary" and the word for "pathway." The term was used along with homeorhesis
Homeorhesis
Homeorhesis, derived from the Greek for "similar flow", is a concept encompassing dynamical systems which return to a trajectory, as opposed to systems which return to a particular state, which is termed homeostasis.-Biology:...
, which describes a system that returns to a steady trajectory in contrast to homeostasis
Homeostasis
Homeostasis is the property of a system that regulates its internal environment and tends to maintain a stable, constant condition of properties like temperature or pH...
which describes a system which returns to a steady state. Architectural Theorist Sanford Kwinter
Sanford Kwinter
Sanford Kwinter is a Canada-born, New York-based writer and world-renowned architectural theorist, and a co-founder of the influential publishers. Kwinter currently serves as Professor of Theory and Criticism at the Harvard University Graduate School of Design...
described the concept of the cherod as "the most important concept of the 20th century."
The word "chreod" also closely describes paths of decision within what Christopher Alexander
Christopher Alexander
Christopher Wolfgang Alexander is a registered architect noted for his theories about design, and for more than 200 building projects in California, Japan, Mexico and around the world...
has called, configuration space
Configuration space
- Configuration space in physics :In classical mechanics, the configuration space is the space of possible positions that a physical system may attain, possibly subject to external constraints...
, his term for what he notes that Stuart Kaufmann calls "fitness landscape." Configuration space is a conceptual landscape which contains all possible outcomes and points of decision within the design of a structure or the growth of an organism or system. Because so very few of the possible outcomes will be good ones, paths to the infinitesimally rare possible and good solutions must be followed to get good results. These paths or, "chreods" appear to be followed automatically in the biological world. (see the cited Kwinter excerpt) By Alexander's theory, because conscious human design decisions do not need to follow these chreods, conscious human design can lead to mixed results. Therefore, he proposes that discovering ways to allow architecture to follow these paths is the best way to get good results in the built environment. Alexander sees his theories of "The Fundamental Process," "structure preserving transformations" and "15 fundamental properties" which he outlines in his four volume work, The Nature of Order
The Nature of Order
The Nature of Order: An Essay on the Art of Building and the Nature of the Universe is a four-volume work by Christopher Alexander published in 2003-2004. In his earlier work, Alexander attempted to formulate the principles that lead to a good built environment as patterns, or recurring design...
as instrumentally shaping paths through configuration space.