Concept

Complex Functional Order

Intro

Complex functional order (CFO) means many parts arranged so that, together, they do something, and the whole only works because the parts are arranged that particular way. A watch, a sentence, a computer program and a living cell all have it.

The phrase exists to stop a common mix-up. People often say, "Nature makes complex things all the time. Look at rivers, snowflakes and hurricanes. So complexity doesn't need a designer." Those things really are complex, in the sense of being detailed and irregular. But none of them has complex functional order. Nothing in a river's bends is arranged to make the river work.

So the useful debate move is to define the term first, and only then ask: is a river complex? The answer is yes, and that is exactly the problem for the objection. A river is complex without being functionally ordered, which shows that complexity was never the issue. Functional order is.

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In full

Complex functional order is a working label for what the design literature describes under several names: Paley's parts "framed and put together for a purpose" (Natural Theology, 1802, ch. 1); Leslie Orgel's specified complexity (The Origins of Life, 1973); Michael Behe's irreducible complexity (Darwin's Black Box, 1996); and the functional information measured by Robert Hazen and colleagues ("Functional information and the emergence of biocomplexity", PNAS, 2007). A system has CFO when it meets four conditions together:

1. Many parts. It is not simple.
2. A function. The whole does something: tells time, carries meaning, runs a program, copies itself.
3. Dependence on arrangement. The function depends on the parts being arranged this way. Rearrange them and the function fails.
4. Not forced by the materials. The physics and chemistry of the parts allow many arrangements and do not dictate the working one. Ink does not force a sentence; amino acids do not force a working protein fold.

Orgel drew the line exactly where this page draws it. "Living organisms are distinguished by their specified complexity. Crystals such as granite fail to qualify as living because they lack complexity; mixtures of random polymers fail to qualify because they lack specificity" (The Origins of Life, 1973, p. 189). Richard Dawkins draws it too: biology, he writes, is "the study of complicated things that give the appearance of having been designed for a purpose" (The Blind Watchmaker, 1986, ch. 1), and he defines "complicated" in that sense as parts arranged in a way chance alone would be very unlikely to produce. Neither author thinks a river belongs in that category.

Step 1, Define it before the example comes up

The order matters. If the objector's example arrives first, the conversation is about whether rivers are complex, and they are. If the definition arrives first, the conversation is about whether rivers have functional order, and they do not.

• Get agreement on the four conditions. Most people accept them at once, because they describe the things everyone already recognises as designed: a watch, a book, software.
• Name the contrast cases in advance. Orgel's crystal (orderly but simple) and random polymer (complex but meaningless) show that order alone and complexity alone are both different from CFO.

Step 2, Ask: is a river complex?

Yes. A river system is detailed, irregular and hard to describe briefly. Its meanders, tributaries and delta channels form branching patterns that no two rivers share.

But it has no complex functional order. Run the four conditions:

1. Many parts: yes, in a loose sense (channel, banks, water, sediment).
2. A function: the river does not do anything that its particular shape is for. Water runs downhill under gravity, and the channel is the path it has worn.
3. Dependence on arrangement: none. Move a bend, add a tributary or straighten a reach, and you still have a river doing exactly what rivers do. Engineers straighten rivers routinely.
4. Not forced by the materials: the reverse is true. The shape is fully accounted for by gravity, terrain, rainfall and erosion, plus chance. That is Orgel's category of law plus randomness, not specified complexity.

The same holds for the other standard examples.

• Snowflakes. The six-fold symmetry is forced by the geometry of hydrogen bonds in ice; the fine detail comes from the temperature and humidity the crystal fell through. Order from law, detail from chance, no function.
• Hurricanes and convection cells. Ilya Prigogine's work on dissipative structures (Nobel Prize, 1977) showed that energy flowing through a system can produce striking patterns. The patterns are real order, but they carry no function that depends on a specific arrangement; they are the shape the energy gradient takes.

Step 3, Is the sediment an interdependent part of a river?

This is the strongest follow-up, and it deserves a careful answer, because flow and sediment really do affect each other. Flowing water picks up, carries and drops sediment; sediment builds bars and banks that redirect the flow; meanders form from that back-and-forth. That is genuine two-way causation.

But causal coupling is not the functional interdependence that CFO requires. Three tests separate them:

1. The removal test. Take the part away. Does the whole stop working? Take the sediment out of a river and it is still a river. Below large dams, rivers run sediment-starved, a condition geomorphologists call "hungry water" (G. Mathias Kondolf, Environmental Management, 1997), and they keep flowing. Blackwater rivers such as the Rio Negro carry very little suspended sediment and are among the largest rivers on earth. Remove the RNA core of a ribosome, where peptide bonds are actually formed, and protein synthesis stops.
2. The substitution test. Swap the part for another of the same kind. Does anything break? Exchange one grain of sand for another and nothing changes. Exchange one amino acid at a key position in an enzyme and the enzyme can stop working.
3. The function test. Is there something the whole does that requires this part in this place? The sediment's position is the result of the flow, not a requirement for it. In a cell, the parts' positions are requirements: the rotor of ATP synthase must sit in its stator for the machine to make ATP.

So yes, sediment and water interact. No, sediment is not an interdependent part in the CFO sense. The river would carry on without it, and nothing about the river depends on any particular grain being where it is. Feedback between parts is common in nature. Parts that need each other to perform a shared function, in an arrangement the materials do not force, are the mark of CFO.

Step 4, Now ask about the cell

With the distinction in place, the living cell is the case that matters.

• DNA stores instructions in a four-letter code whose sequence the chemistry of the bases does not determine, and the cell reads it through a separate translation system. See DNA.
• The ribosome reads that code and assembles proteins, and is itself built from proteins and RNA that the code specifies.
• Molecular machines such as ATP synthase and the bacterial flagellum have parts that pass all three tests in Step 3. See Irreducible Complexity.

Every condition holds: many parts, a function, dependence on arrangement, and an arrangement the materials do not force.

Step 5, What produces it?

The design inference comes in here, and it should be stated carefully.

• In ordinary experience, CFO comes from minds. Every watch, book and program whose origin we know was made by an intelligence. Stephen Meyer builds this into an inference to the best explanation for the origin of biological information; see Signature in the Cell Argument and Information Argument.
• Law and chance produce order and complexity, but not CFO, which is what the river, the snowflake and the hurricane illustrate. That is why they are the wrong counterexamples.
• Natural selection is the serious alternative, and it should be faced directly. Selection can refine function in systems that already reproduce. It cannot explain the first self-replicating system, because selection needs replication before it can begin. That moves the question to the origin of life; see Abiogenesis and Argument from Origin of Life.

Honest limits

• The river test removes a bad counterexample. It does not by itself prove design; Step 5 does that work, and it is contested.
• "Function" needs care. A river plays roles in an ecosystem, and someone may call those functions. CFO concerns whether the river's internal arrangement is required for something the river does, and it is not.
• The four conditions are a working definition for debate. Measuring them precisely is the job of the technical literature (Dembski's specified complexity, Hazen's functional information), which this page points to rather than replaces.

Scholarship

Published academic works this page draws on, each matched to a publisher, index or library catalog record.

• Michael J. Behe, Darwin's Black Box (1996). Open Library
• Richard Dawkins, The Blind Watchmaker (1986). Open Library
• Robert M. Hazen et al., "Functional information and the emergence of biocomplexity," Proceedings of the National Academy of Sciences 104 (2007). doi:10.1073/pnas.0701744104 PubMed 17494745 open access
• William Paley, Natural theology: or, Evidences of the existence and attributes of the deity, collected from the appearances of nature (1802). Open Library

See also

• Specified Complexity Argument, Dembski's formal version of the same distinction
• Specified Complexity, the concept hub for Orgel and Dembski's criterion
• Irreducible Complexity, Behe's interdependent-parts criterion
• Irreducible Complexity Argument, the debate-prep argument
• Signature in the Cell Argument, Meyer's inference from biological information
• Information Argument, information as the signature of mind
• DNA, the code at the center of the cell
• Abiogenesis, why selection cannot explain the first replicator
• Evolution, where natural selection fits
• Laws of the Universe as Witness to Design, design in the laws themselves, as distinct from design in arrangements
• Richard Dawkins, who concedes biology's appearance of design
• Michael Behe, Stephen Meyer, William Dembski, the main design theorists