by Manolis Spanakis

Wednesday, 7 September 2011

Logic of the Intelligent Design

Dissection of the internal logic of the Intelligent design argument for the origin of species.

The 18th-century clergyman William Paley likened living things to a watch, arguing that the workings of both point to intelligent design (ID). The old argument is that complex things with a special function, like a watch or a living organism, cannot have arisen spontaneously by chance and, therefore, must have been created by an intelligent designer; the watch by a watch craftsman and life by God. The argument is repeatedly proposed as a logical proof for the existence of God and against the Darwinian theory of natural selection. Michael Behe, American biochemist, author, and intelligent design advocate, published a letter in New York Times (2005) where he rephrases the argument using the metaphor of the sculpture of Mount Rushmore: "Unintelligent physical forces like plate tectonics and erosion seem quite sufficient to account for the origin of the Rocky Mountains. Yet they are not enough to explain Mount Rushmore." The ID argument is based on the supposition that some biological systems are so complex that they can only function when all of their components are present. Such systems could not have evolved from a simpler assemblage that did not contain the full machinery. They call this complexity "irreducible complexity" (IC). In all, we can all recognize ID from its complexity and because the living organisms present irreducible complexity they could not have evolved by natural selection but must have been created by an intelligent designer; guess Who...

The argument can be summarized:
  1. Intelligently designed objects (watch, sculpture) are recognizably complex
  2. Therefore, any other recognizably complex object must also be intelligently designed.
I will show that the first statement, the assumption, is false and the second statement, the conclusion, is uncertain. In human logic, every statement has a contraposition, an inversion, a conversion and a contradiction. In practice, mathematicians and scientists use these transformations of a statement in order to evaluate its truth. The contraposition has always the same value of truth as the original statement. If the contrapositive is true then the original statement is also true, and vice versa. If the contrapositive is false then the original statement is also false, and vice versa. The truth value of the contradiction is always the opposite of that of the original statement. If the contradiction is true, then the original statement is necessarily false; if the contradiction is false then the original statement is necessarily true. In mathematics, and in everyday (straightforward) logic, proving that the contradiction is false is equivalent of proving that the original statement is true, and vice versa. Inverse and converse statements may have either the same truth value as the original statement or the opposite opposite truth value. If the original statement is true then the inverse statement may be either true or false and so may be the converse statement. The same ambiguity (ignorance) about the inverse and the converse statements appears when the original statement is false. Therefore, neither the validity of the inversion nor the validity of the conversion may be used for proving the validity of the original statement.

  1. If a statement is true, then its contrapositive is true (and vice versa).
  2. If a statement is false, then its contrapositive is false (and vice versa).
  3. If a statement's inverse is true, then its converse is true (and vice versa).
  4. If a statement's inverse is false, then its converse is false (and vice versa).
  5. If a statement's contradiction is false, then the statement is true (and vice versa).
Table 1: Summary of the logical relationships between statements in an example of common logic.

Statement nameExample statementTruth value
Original statementAll red objects have colorTRUE
ContrapositionIf an object does not have color, then it is not redTRUE
InversionIf an object is not red, then it does not have color?
ConversionIf an object has color, then it is red?
ContradictionThere exists a red object that does not have the properties of colorFALSE

Table 2: Text from Table 1 where the word "red" was replaced with the word "ID" (intelligent design), and the word "color", with the phrase "recognizable complexity".

Statement nameIntelligent Design (ID) statement
Original statementAll ID objects have recognizable complexity
ContrapositionIf an object does not have recognizable complexity, then it is not ID
InversionIf an object is not ID, then it does not have recognizable complexity
ConversionIf an object has recognizable complexity, then it is ID
ContradictionThere exists a ID object that does not have the properties of recognizable complexity

In the above Table, the Intelligent Design argument consists of two statements highlighted in red:
  1. Assumption: All intelligently designed objects have a recognizable complexity.
  2. Conclusion: If an object has recognizable complexity, then, it is intelligently designed.
Note that the second statement, the conclusion, is the converse of the first statement, the assumption. Even if the assumption is true, the converse conclusion is not necessarily true. In this case, even if all intelligently designed objects could be recognized as such by their particular complexity it does not necessarily follow by "straightforward" logic that any recognizably complex object is intelligently designed. But, is the assumption of the Intelligent Design argument true in the first place? To test its validity, we may test the validity of its contradiction instead : It is sufficient to find a single intelligently designed object that does not look as if it ware intelligently designed. Here is a small list:
  1. My computer. Do not laugh, some of the programs I am using seem to have been written by monkeys; we all have this impression sometimes. Stated formally, all those things that did not ever function as they were designed to; the failures of human intelligent design. This category includes all those objects that make you wonder "who, the hell, has designed them?"
  2. An English garden. Anglo-Saxons design gardens to look as if they were natural. Sometimes they succeed.
  3. The shape of cities. Cities are limited by natural barriers (limits of intelligence?) and their random-looking shape is actually the result of intelligent urban design.
  4. Primitive, or contemporary organic, agriculture. Gatherers, hunters and animal farmers apply intelligent methods that may not always attract the attention of an objective observer. So do many animals, social or not, to capture their prey or to escape a predator.
  5. The products of intensive agriculture. An apple produced using modern methods and technologies looks identical to a wild apple. Except that wild apples do not usually make it to the market.
  6. National parks. Natural looking ecosystems that are protected by intelligently designed legislation in order to reverse negative evolutionary trends.
  7. Non-protected ecosystems. These suffer the consequences of intelligent design.
  8. Modified ecosystems. Dried lakes, cultivated deserts. Burned forests.
  9. Selectively bred animals and plants.
  10. Genetically engineered or cloned organisms.
  11. Artificially made natural chemicals.
  12. PCR. An intelligently designed biochemical reaction that may be interpreted as a simple natural process.
  13. Artificial snow. Artificial ice. Liquid nitrogen. Broken rocks (stones). Any purposeful physical transformation of natural materials.
  14. Crime that escapes justice. The criminal designs the scenario so that the crime looks like an accident.
  15. Pollution. Changes in the composition of environmental elements may have climatic as well as intelligent design origin.
  16. Craters of  bombs or other explosions. Mines.
  17. Radiation, electricity, radio waves. Invisible products of intelligent design that require sophisticated methods to be recognized.
  18. Medical treatment, vaccination, poisoning. Pest and parasite control. Intelligently designed methods and products for prolonging or shortening the life of individuals.
  19. Effects of prayer. If you believe in the existence of such effects, the non-believer still does not recognize them and thinks they are products of chance.
  20. An almost straight line on the beach (showing the north). Some objects of intelligent design are quite simple and their origin, purpose and function may be difficult to establish.
  21. ...
All this is to say that the contradiction of statement 1 seems to be true: there exist at least one product of intelligent design that does not have the properties of recognizable complexity (it is not immediately recognized as product of intelligent design). Therefore, the original statement 1 is false (though its conversion may still be true).

Irreducible Complexity of the ironing system

Both, complexity and intelligence are quantitative and subjective variables. The degree of complexity of an intelligent design depends on the distance of the observer from the object and also on how well the observer understands the function of the object. Thus, both variables may have different values for different observers. My dog is more interested in his ball than in my computer and prefers me to cook than to calculate. The term "recognizable complexity" is rather subjective and vague: recognizable by whom? how complex? what is the "object" in a system where everything is inter-dependent? should I measure the complexity of my electric iron alone? or should I include the nuclear power station that produces the electricity for my iron to function? what about the textile industry that gives my iron the very reason for being?


The paradigm of complexity for the proponents of the ID hypothesis is what they call "irreducible complexity" (IC): a system with IC is a system where all parts are necessary and sufficient for the system to perform its function; removal of any of the parts will cause the system to fail. All irons have a flat iron surface by definition; electric irons commonly have a heating element; some of them also have a power indicator, others, a potentiometer that regulates the heat and/or a steam producing sub-system. The designer of electric irons was probably inspired from a cattle (or vice versa). When the heating element of my iron fails, the iron becomes useless. It also becomes useless when the handle brakes, when the flat surface is bent, when there is a loose contact in the socket, when the central fuse burns or when there is a strike of power plant workers for higher salaries. But, do I really need to iron my own clothes myself? and how essential is for cloths to be ironed anyway? In the "archeological" record, the first irons appeared roughly at the same time as the textile industry. They were extremely simple and very robust objects literally made of iron. What made them functional was their shape;  a flat surface and a handle. They did not require electricity (which did not exist then). Modern programmable irons have very similar shape, contributing to their essential functionality, but they are far more complex objects and far more prone to overall failure. A distant observer may well understand that, if going to work with ironed cloths were important for my own survival, the survival of my family and/or the survival of the society as a whole, then, a healthy state economy that allowed dissent payment of power plant workers would be a better solution than simply improving the life expectancy of the electrical resistance of my own private iron. Not only my own iron, but also everybody's iron would function for longer periods. If the resistance of my own iron failed, I could have my cloths ironed elsewhere or use a spare iron. For another distant observer, maybe, an even better long term solution would be to invent fabrics that do not need ironing. All irons, even those with awesome design, would become redundant and would disappear all together. Some representative specimens of iron design and ironing technology would be fossilized and exposed in museums.

A Marxist observer may explain the ironing system as a byproduct of a class struggle among blue collar workers of the household, textile and power industries, form one hand, and the white collar class, from the other. He may predict alliance of white collars with textile workers for the final extinction of iron makers. A capitalist observer would, instead, foresee profit in an alliance of household and textile industries and predict fusions towards giant monopoles that will produce fabrics requiring ironing for ever. Ironing-free fabrics will never be invented. The household-textile industrialists will eventually invest in power stations to produce the power required for ironing cloths by white collars. And the whole system will diversify and grow bigger and bigger. A poor creationist observer, obsessed with the marvel of the design of a thermostatically controlled spring resistance of a contemporary or fossil electrical iron, would think that if you removed the thermostat, the spring or the plug, the system would cease to function; therefore, thermostats, electrical resistance springs and plugs must have been designed simultaneously by an intelligent designer to function in concert for the purpose of ironing. But he will fail to recognize that a thermostat, an electrical resistance and a plug may be put together to create a myriad of functionally diverse objects and that the parts of an iron have nothing in particular to do with ironing. He will also fail to recognize that what makes an iron ironing is its elementary shape and what makes ironing useful is a particular type of fabric that has not been, and will probably not be, around for very long. The future evolution of the ironing system will show which observer was right.

Irreducible Complexity of the bacterial flagellum

In the living world, modern creationists model irreducible complexity with the example of a bacterial flagellum. Some 15 components of that system are thought to be necessary for bacterial locomotion because these are commonly found in all the bacteria presenting motility; but flagella (like irons) also have components that are specific to some bacterial species and are, therefore, dispensable from other species. Some species of bacteria do not have flagella at all. A plausible reason why some bacteria have flagella is that they need to move to particular directions. Why? probably because their nutrient or physical resources are scarce and their nutrient or physical environment is not homogeneous in space and time. Bacteria that live in rich homogenous environments do not, logically, need locomotion. If creationism were a science, and the Intelligent Design, a scientific hypothesis, then they should be able to predict:
  1. If only irreducible complexity requires a designer, how did the other versions of flagella arise?
  2. Or, does the He also designs dispensable elements?
  3. Why some of the indispensable elements also appear to perform other functions in bacteria lacking flagella?
  4. Are those elements also indispensable in their other functions outside a flagellum?
  5. Did the Designer design Irreducible Complexity only? or entire organisms with their dispensable elements?
  6. Did He design ecosystems or at least their indispensable species?
  7. Are irreducibly complex systems expected to micro-evolve?

Irreducible Complexity of archeological systems

The Parthenon, a masterpiece of human irreducibly complex design, was reduced down to scattered stones due to an "unintelligent" explosion in 1687, when  the Venetians under Francesco Morosini attacked Athens and the Ottoman Turks fortified the Acropolis and used the temple as a gunpowder magazine. Since, some of the Parthenon's fragments have been used in other buidings. Today, not only can specialised archeologists recognise some stones as fragments of the ancient temple but they can also tell which other fragments they fit and which fragments are still missing. Recognition of the "design", whether on Parthenon fragments or in other found objects, does not at all depend on the intelligence of the designer nor on degree of complexity of the object. It only depends on the intelligence of the observer. The archeologist Manolis Andronikos could recognise some bones he found as being those of King Philip II of Macedon; my dog would have taken them as any other edible bones. The King, himself an ex-Irreducibly Complex system, was reduced to bones and became part of another Irreducibly Complex system known as his tomb. Andronikos did not expect to find Philip II of Macedon in person in order to conclude that he had just discovered a royal tomb. Instead, he based his theory on a irreducibly complex system of knowlegeable historical and geographical associations. Some of the elements of that system are essential for formulating a convincing theory and some are only accessory. The heart of the King was essential to him while he was in power but was completely dispensible from the Intelligent Design of his royal tomb; the bones alone would do. The concept of Irreducible Complexity is, therefore, not a property of the object itself but a construct of human mind. Essential parts of one complex system may become essential parts of another complex system and be disposed of the first in a very natural way.

If IC then ID, therefore, If Not IC Then Not ID

The contrapositive of statement 1, "If an object does not have Irreducible Complexity (recognizable complexity), then it is not Intelligently Designed", is also rejected.  Here are some examples where this contraposition sounds absurd:
  1. If I smell burning wood, it is impossible that someone has made a fire for cooking, because wood fire is not complex enough to be considered as intelligently designed.
  2. If I see snow on the ski station, it is impossible that the snow was just put it there for me to ski on, because snow is not sufficiently complex to have been made by man.
  3. If I see a straight line on the beach, it must have been drawn by chance, because a line does not contain any information about the designer nor its purpose.
  4. Most people are not capable of detecting the presence of radiation, electromagnetic waves,  pollution etc., never mind appreciate their complexity and understand their origin.
  5. The rain, a by excelence random, unintelligent phenomenon, may be removed from the ecosystem because unintelligent phenomena serve no purpose.
  6. All those biological systems that can afford to lose one part and still function may have not been designed. Examples of this internal inconsistency is a man having his kidney removed, all knock-out transgenic mice, a plant that has lost all its leaves, a global ecosystem that has lost its dinosaurs.
Replacement of the concept of "recognizable complexity" with the concept of "irreducible complexity" bears catastrophic risks to the intelligent design argument. It would mean that atoms, simple molecules and the entire global ecosystem consisting of oxygen, nitrogen, carbon dioxide, water and the elements of soil are irreducibly complex. If you remove an electron from an atom, the element ceases to exist. If you remove an atom from a molecule, the molecule ceases to exist. If you remove any one of the elements of the global ecosystem (say, remove the water), the whole life will collapse. Instead, genomes, organisms, populations, species and ecosystems are not irreducibly complex. You may remove genes from genomes, remove tissues or organs from individuals, cut a tree, remove individuals from populations or species from ecosystems. You may remove all dinosaurs and life will cover the gap. In other words, irreducibly complex are, paradoxically, only the simplest elements on earth. Life, at least its more complex forms, is not irreducibly complex and, hence, is not necessarily the product of intelligent design. Other theories are required.   Table 3: Text form Table 1 where the word "red" was replaced with "irreducibly complex" (for recognized complexity) and the word "color", with "ID" (for intelligent design properties).

Statement nameIntelligent Design (ID) statement
Original statementAll irreducibly complex objects have ID
ContrapositionIf an object does not have ID, then it is not irreducibly complex
InversionIf an object is not irreducibly complex, then it does not have ID
ConversionIf an object has ID, then it is irreducibly complex
ContradictionThere exists a irreducibly complex object that does not have the properties of ID