Why the creationist argument that “irreducible complexity” disproves evolution is utter nonsense

May 10, 2006 | By | 26 Replies More

Irreducible complexity refers to a system (e.g., a living organism) in which the various parts work together to produce a given function, such that the function will not occur if any of the parts is removed.  Creationists claim irreducible complexity disproves evolution.

Evolution refers to the natural adaptation of a species to its environment over time, usually going from a more simple or basic form to one that is more complex or advanced.  In other words, evolution refers to genetic specialization over time, as time moves forward.

Unlike the case with evolution (progression from simple to complex as time moves forward), irreducible complexity starts with a highly evolved, complex organism and proposes to work backwards in time, subtracting pieces.  “Look,” the creationist will say, “if we turn time backwards, by subtracting pieces from a complex organism, the organism will stop functioning.  Therefore, evolution is disproved.”

Oh really?  If evolution is about genetic progression (from simple to complex) as time moves forward, and irreducible complexity is about genetic regression (from complex to simple) — essentially going backwards in time — then isn’t it obvious that evolution and irreducible complexity have absolutely nothing to do with each other?  Far from disproving evolution, irreducible complexity is a total non sequitur.  The essence of the creationist “irreducible complexity” argument is that evolution can’t run backwards, therefore evolution is disproved.  What utter nonsense.


Category: American Culture, Current Events, Evolution, Meaning of Life

About the Author ()

Grumpypilgrim is a writer and management consultant living in Madison, WI. He has several scientific degrees, including a recent master’s degree from MIT. He has also held several professional career positions, none of which has been in a field in which he ever took a university course. Grumps is an avid cyclist and, for many years now, has traveled more annual miles by bicycle than by car…and he wishes more people (for the health of both themselves and our planet) would do the same. Grumps is an enthusiastic advocate of life-long learning, healthy living and political awareness. He is single, and provides a loving home for abused and abandoned bicycles. Grumpy’s email: grumpypilgrim(AT)@gmail(DOT).com [Erich’s note: Grumpy asked that his email be encrypted this way to deter spam. If you want to write to him, drop out the parentheticals in the above address].

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  1. How are Humans Better? | Dangerous Intersection | May 8, 2010
  1. Erich Vieth says:

    I assume that the reverse path, one of merely subtracting out phenotypic pieces, is likely a different path then the forward path, not merely a reverse path. Traits can come and go on the way "up," serving as scaffolding for further development, then disappearing (I'm thinking of nonfunctional eyes found in cave animals who were not always cave animals, for example).

    Climbings Dawkins' Mount Improbable, that slow grade on the backside of the cliff is a different path than jumping off the cliff in an attempt to see things in reverse.

  2. Jason Rayl says:

    That term "progress" is the thorny part. It's so easy to think in those terms, but it's misleading, and that's where debates between Creationists and evolutionists bog down. "Complexity" does not equate to Progress, which is culturally loaded to mean "toward something better." If you grant that notion, then it gets harder to teae apart the nonsense from the factual arguments. "Better" implies advancement toward a goal and that leads to a Plan which implies a Planner.

    Better is the arguing in opposition to entropy, which is where all creationists trip up. Entropy applies (in the simplest terms) to closed systems, wherein complexity always dissolves over time. Earth and its environment are not closed systems. The energy required to drive variation comes daily from the sun in virtually limitless supplies (for our purposes) which drives competing biomes which intrude on each other and over time results in higher complexity.

    The problem creationists have with this is that it leaves out entirely the idea that Human Beings are the pinnacle of so-called Creation. To admit that there is no "progress" or "goal" is render us just one more species that can be (and probably will be) replaced by something else.

  3. grumpypilgrim says:

    Not only is the reverse path of "irreducible complexity" very different from the forward path of evolution, but the creationists even go one step even deeper into absurdity. They don't merely replace one of the highly-evolved "complex" body parts with a less evolved part, they eliminate the part altogether. That's what they mean by "irreducible complexity" — that each body part is so well integrated with the other body parts to form a unified whole that you can't eliminate any one of the body parts without also losing the functionality of the unified whole. It's like saying, "See, if we hack off one of the hind legs on that kangaroo over there (in their example, creationists use the spiral tail of a bacterial flagellum), then it can't jump anymore and will quickly be killed by dingo dogs; therefore, the roo must have been designed by an intelligent creator and we have disproven evolution." Obviously, amputating one leg of a kangaroo would be very bad news for the roo, but it would prove nothing at all about evolution nor even about so-called "intelligent design." Irreducible complexity is merely one of several efforts by creationists to cloak their religious beliefs with science. I suspect that's why they use the bacterial flagellum as their example rather than, say, a kangaroo — because flagella are familiar only to microbiologists, so it makes their example (and, thus, the notion of irreducible complexity) seem like a recent scientific discovery. The truth is that irreducible complexity is not a new concept at all; creationists just keep tarting it up with newly-discovered critters to try to give new life to their ridiculous, worn-out argument.

  4. Edgar Montrose says:

    Let's apply this concept to an evolution that we have seen happen in our own lifetimes — Microsoft Windows.

    We can start with PC-DOS, a rudimentary operating system that worked on only one machine. It evolved into MS-DOS, that worked on only one type of machine. Then it evolved into Windows 3.1, with more features that made the PC more successful. Then there was Windows 95, that abandoned the 16-bit constraints in favor of 32-bits, though it still maintained 16-bit compatability (consider it a vestigial organ). By Windows ME, 16-bit compatability had been abandoned. Somewhere along the line Internet Explorer, Outlook, Media Player, and others — that had previously been standalone applications — became assimilated so deeply into the OS that, when anti-trust charges were leveled at Microsoft, they claimed that Windows had "irreducible complexity"; that removing Internet Explorer, for example, would cause the OS to stop functioning.

    If it is assumed that Microsoft's claim of irreducible complexity was true, does that prove that Windows didn't evolve from PC-DOS?

  5. Erika Price says:

    Also, every example of irreducible complexity that the ID nuts have cited– bacterial flaggelum, blood clotting cascade, and others– fails when placed under REAL scientific scrutiny. A pointless nonsequitur in itself, irreducible complexity does not even exist.

  6. grumpypilgrim says:

    Jason's comment raises a couple of new points I'd like to follow-up on. The first is the tendency of creationists to play word games in their effort to insert a Plan (and thus a Planner) into nature, by suggesting that evolutionary change over time (usually toward increased genetic complexity) is equivalent to "progress toward a goal" or something that is "better" than what came before. But, as Jason points out, evolution involves no such value judgments. Species simply adapt to their environments while, correspondingly, environments adapt to their resident species. Over time, this mutual adaptation tends to increase the complexity of both, because survival tends to favor species that find specialized niches or, more broadly speaking, species that find increased symbiosis with other species. We see a similar adaptation process in human careers: jobs have become more specialized as work environments have become more complex, and the interaction of the two keeps driving both toward greater complexity. Does this imply "progress" toward a "goal," or that humans (or other species) today are any "better" than our ancestors? Of course not. We are merely the current crop struggling to survive and reproduce in today's environment. Ironically, many Fundamentalist Christians seem to burn with a belief that humans today are *worse* than our ancestors (witness their many attempts to reject modern life and return to yesterday's lifestyles), but that too is merely their own value judgment. Neither nature nor evolution necessarily involve a species making "progress" toward a "goal, or becoming "better" in any absolute sense. Indeed, increased complexity and specialization cannot be said to be "better" in any absolute sense, because they usually carry with them an increased risk of obsolescence and extinction (as we have seen in both nature and human jobs).

    As regard's Jason's second point, indeed creationists often trip themselves over the concept of entropy. Their entropy argument is just another red herring, which they use to try to cloak their argument with the words of science (just like irreducible complexity). Their argument usually goes like this: entropy (i.e., the Second Law of Thermodynamics) states that the Universe (or any other closed system) tends toward chaos, but evolution says living creatures tend toward greater complexity (which is the opposite of chaos); therefore, evolution must violate entropy. Of course, as Jason points out, this creationist argument is nonsense, because entropy refers to a closed system (i.e., a system into which no energy is added), but life on earth is not in a closed system: the earth continuously receives energy from the sun, and this energy is what drives the evolution engine. Thus, contrary to the creationist argument, evolution does not violate entropy.

    (Note: creationists also try to refute evolution on the basis of the First Law of Thermodynamics; namely, conservation of matter and energy. They argue that the Big Bang theory of how the Universe began represents a spontaneous creation of matter and energy, which violates the First Law of Thermodynamics. The obvious error in their argument is that humans know nothing about the quantity of matter and energy that existed before the Big Bang, so there is no way to know if the Big Bang conserved matter and energy, or not. Thus, their argument is nonsense. For more creationism-busting arguments, visit this excellent website: .)

  7. grumpypilgrim says:

    I'm sorry, for some reason the blog blanked out another of my web links, so I'll try again. This is the website for more creationism-busting arguments:

  8. Jason Rayl says:

    Just an observation about grumpypilgrim's last point (First Law of Thermodynamics). We don't know from whence all this Stuff came from, we can only surmise. Note, whenever a scientist or a scientifically-oriented persons says "We Don't Know", it is the practice of the fundie to stick God into that space.

    One result of this would be–could be–the response that "Well, according to that, you mean to say that God is a Gray Area?"

  9. Erich Vieth says:

    "Creationists are still trying to salvage irreducible complexity. This generally involves a bait-and-switch game. Today, for example, the Discovery Institute tells us that the evidence of dolphins does not touch the argument for irreducible complexity. See, what you have here are two different irreducibly complex systems, with one that just happens to have an extra part. Just think about bicycles…"


  10. George says:

    Windows did not evolve in the manner that living organisms evolved. Windows had an intelligent designer (many of them in fact called software engineers). Each generation of Windows improved BECAUSE the software engineers added to and improved the code base.

    So this reply of Windows evolving is a foolish argument. In fact, the Windows evolving supports ID.

    ID opponents present various unconvincing examples like the bacterium losing its flagellum doesn't prove anything.

    How about the feather? How about the fact that somehow the feather evolved on a bird which just happened to have hollow bones?

    People that believe that all life evolved by random chance into all that we see have incredible faith in evolution. I mean, to not even have witnessed a single instance of macro-evolution, and yet believe this, is amazing. How is believing in this, and believing that cars spontaneously evolved from bicycles any different? You can make the argument that the form is similar. Both have wheels. Both go somewhere. Both have a means of locomotion.

    • Erich Vieth says:

      George: I will try to say this without sounding condescending, but that might be impossible. Do you know how the characteristics of "scientific theories"? Are you really familiar with the evidence on which the scientific theory of evolution is based? I suspect not. Most certainly, based on what you've written, you are not doing science. Rather, you are invoking the "It's so amazing that I can't imagine that it would be true" reaction. Contrast what you are doing with real science. Have you actually read a quality book on the basics of evolution by natural selection?

      Try reading What is Evolution, by Ernst Mayer (2002) http://www.amazon.com/What-Evolution-Ernst-Mayr/d

      Or read Richard Dawkins' new book, The Greatest Show on Earth. http://www.amazon.com/Greatest-Show-Earth-Evidenc

      Circumstantial evidence can make tremendously strong cases in the courtroom and out in the world. I'm sure you have no trouble believing that electricity powers your computer, even though you have never seen it. "It's so amazing that I have a hard time believing it" won't fly in the face of the many types of evidence you CAN see, even though evolution happens too slowly to stand there and watch new species evolve. Give the real evidence a real chance before jumping to conclusions that science is making the same types of wild leaps as you'll find in religions.



  11. Dan Klarmann says:

    George is also missing the Windows point. Windows 7 (for example) did not have an intelligent designer. It came from many generations of selection from essentially random changes created by thousands of memetic exchanges, mutations, cross-linking, and interbreeding. Many parts of Windows came from Macintosh and CP/M and OS/2 and Next and Linux phenotypes (manifestations of genes). Often not the best parts, either.

    The fact that each of the millions of active participants in its evolution all consider themselves to be intelligent does not indicate the there was a single intelligent creator. The more minds one adds to a crowd, the lower the overall functional IQ.

    The recent selection pressure of people (the environment in which an O/S lives) resisting Vista in favor of the older XP caused this branch to die out and Win7 to quickly replace it.

    There are 3 geni of Microsoft O/S: DOS, NT, and Longhorn. Under DOS came the species DOS, Windows, Win95/98, and WinME. Under NT came species NT thru 4.1, Win2k and WinXP. Longhorn has species Vista and Win7 (so far). Each species has several breeds, some because of gradual evolution (service packs and updates), and others because of different environmental pressures (desktops, servers, netbooks, embedded apps, etc).

    Because each species tends to crowd out all others in a given niche (all Wintel boxes), older species go extinct.

  12. George,

    What qualifies as "witnessing macro evolution?" Quite a lot has been documented. (There's a species of lizard in the Adriatic indigenous to a single island. A group of them was transplanted to another island decades ago and have shown a high degree of speciation, very quickly and very dramatically. Recently a previously unrecorded branch of the monitor lizard family was documented in an area where none previously had been seen.)

    But to assume that a process which takes place and is witnessed on the micro level (E.Coli for example) simply stops once a certain level of complexity is achieved is absurd. You would have to explain why it happens in the first instance and not the latter.

    Furthermore, "random chance" is a problematic statement. Random and Chance do not mean the same things. It has been shown repeatedly that certain chemical processes WILL happen given the proper circumstances, and that said circumstances occur regularly. The random occurrence of something that WILL happen changes the emotional implications of your objection to something that is not quite as miraculous as you'd like it to be.

  13. NIklaus Pfirsig says:

    Methinks George is implying the Bills Gates is a aGod….

    But wait aminute!

    MS-DOs was a slightly hacked version of QDOS, which was based on a stolen alpha grade version of CPM-86, which was a 16-bit version of CPM-80.

    CPM-80 was written, along with the PLM programming language by Gary Killdahl, Founder of Digital Research.

    PLM was inspired by parts of IBM's PL/1, an incredibly complex programming language. PLM reduced the complexity of a huge editor-compiler-assembler chain to a tightly coder 8-bit compiler.

    Does this mean that Gary Killdahl is God? What about the Assembly language that the core IO and math routines were written in? Or better yet, the machine codespace the defined the opcodes for instruction set of the intel 8080 was designed by Bob Noyce, so ie he GOD?

    Let's not forget the work of all the engineers and mathmaticians at Harvard, MIT, Bletchly Park, and the works of von Neumann, Boole, Hollerith, Picard, Lukasiewicz, Babbage, Pascal and many more.

    Did any of these people and organizations decide that there would be a grand plan culmination in that bloated, crappy piece of software called "Windows"?

    NO. They were and are part of the environment that Windows wvolved from. But this is a tangent, because modern operating systems are not irreducibly complexity.

    Is Windws irreducibly complex? Let me ask a better question. Are modern Graphic Operating systems irreducibly complex?

    There are dozens of operating system in use today other than Windows. There are OS-X, and Linux of course, there are also PalmOS, Symbian, RTOS, MinuetOS, Netware, MVS, OSVS, zOS, Plan9, QNX.

    Even Microsoft has versions of windows that are less complex than the desktop versions of Windows 7. They include the various mobile versions of windows, embedded version of windows, the pocket PC versions found on the Zune and in many GPS devices.

    Even this is a moot point, as the software has no physical essence, it is simply the long detailed list of instructions. The electrons in the circuits of the computer, the magnetic domains on the hard drive, the hardware the is needed for the program to run was not called into existence out of nothingness at the whim of the programmer.

    When the programmer "instantiates" an "object" in a program, he is creating something out of nothingess, not magically calling somethign into existence, but instructing the compiler to copy a set of patterns in the computer's memory, where changes (overrides) can be made without corrupting the original pattern.

    Intellectual property has no physical attributes. There is a simple way to prove me wrong on this, however.

    The next time you buy a new car, will you please burn me a copy for free?

  14. Two points from a Christian perspective. I do not, nor have I ever, bought into the Intelligent Design Argument. I have advised my Christian friends to avoid it. If they want to understand science better, they're just going to have to learn a bit about it themselves. ID simply isn't science. It is, however, a decent philosophy. In other words, when I look around, everywhere, I see evidence of a designer. It just seems that way to me. I really don't care what you reflect on when you look at a sunset or a baby, but I think, "wow, God is great." Point #2: Jason commented about progress etc. While I agree that we should choose our words carefully when discussing these issues, do not fall into the trap of ignoring the obvious. Humans are different than all the other creatures on this earth. They are "better" if you will. We wouldn't be having an argument over a creator at all if this were not true. The evidence for this is everywhere, including this website…sometimes.

  15. Dan Klarmann says:

    Humans, like all other species, are different than all other creatures on this Earth. "Better" is a value judgment, generally declared without defining the parameters. Dolphins are better at swimming, geckos at climbing, bats and dogs at hearing, elephants at monogamy, bonobos at conflict resolution, and so on.

    The designer of humans has short-changed us at every turn, God bless us.

  16. Dan completely misses my point, and, in the process highlights my central complaint about your writers. I believe that you do know what I mean when I say humans are "better." It's a colloquial phrase meant to denote a whole group of things that raise the human animal above the others. Obvious things that all y'all know about. Because that idea smacks of religion, you feel that you have to cut it down. Yet, in some other context, you'd have no trouble at all speaking of our superiority. I am not injecting value and morals into the argument, I'm claiming that from a strictly scientific viewpoint that humans are ***** (you fill in the blank with a word that makes you comfortable in your non-religious world.) I suggest reading the latest on origin of language theory to get some insight into this. These scientists will tell how really very much ****** we are.

  17. Richard Hudson wrote:—"Because that idea smacks of religion, you feel that you have to cut it down."

    Well…how can it not?

    Look, of course I know what you mean. Humans do stuff no other critter does. We build, we observe, we parse to nth decimal places all manner of phenomena no other life form of which we are familiar even thinks of in terms of phenomena.

    But "better" is a value judgment based on the idea of telec reasoning, basically that things (especially living things) are built or exist for a purpose (a telos), which can only be true if, in fact, we were made for a purpose—an end purpose, that is, designed to meet some a priori requirement. It would then be an applicable metric to all things—some entities being "better" than other entities at certain things and therefore better able (more suited) to reach that stated goal (whatever it may be).

    So in that sense to talk of us being Better by definition smacks of religion because there is no other way for it to make overall sense.

    If not, then each entity sets it own standard and gauges all others accordingly, which hews closely to solipsism.

    Between these two extremes, it is probably accurate to talk about better in certain terms while being continually aware that we're being arbitrary. Because the only way to make an objective claim for "better" or "worse" would be to imagine (or ask, if we could) if other life forms would swap places with us (while maintaining their unique albeit distantly-related phylogenic manifestations). Would we, in colloquial terms, be envied for what we can do by, say, dolphins or tigers or squids?

    Having said all this by way of stripping the term of its inevitable hidden freight, just the fact that we can posit such a scenario does indeed, I'll admit, seem to privilege us in a rough hierarchy of abilities.

    Shorn of its religious baggage, though, it also adds new freight, which is the inescapable responsibility of an entity that knows it can understand, knows it can manipulate its own environment so as to nearly exempt itself from the run-of-the-mill contextual pressures of life, knows it can determine form, function, and felicity of almost every other creature coexistant with us to then be damned careful of the kind of hubris that can emerge and envelope us with the concession that, yes, we are Better. That capacity sort of takes us out of the kind of "ultimate plan" thinking that seems the bastion for many (not all) religious folks who like the idea that we were created "better" but are still locked into the overarching telos of the Designer so that no matter what we do it will somehow all work out in the end—in other words, because we are "better" we've kind of wrecked that sort of thinking and if we don't take care to make sure things work out for the best in the end, then things won't work out well.

    So the reluctance on all parts to accept the assignation of the term "better" I think stems from an innate sense of this responsibility and a recognition that if we are, in fact, better we have to date made a piss poor showing of our potential in many, many ways.

    • Erich Vieth says:

      Mark: This sort of human superiority talk brings to mind the "Chain of Being," a topic I addressed in a post called "My Life as a Sponge." I would agree that we are exquisite animals with some abilities that no other animal has. We are certainly "better" in the sense that we we have survived and multiplied to fill all corners of the Earth; that puts us right up there with many species of bacteria, and with cockroaches and mice, of course.

      We are better than the other animals only if we, as you suggest, invoke a frame of reference, and in order to make sense of the claim of "better" we have an obligation to make explicit that frame we are invoking. We are better in that we can read, but that invokes the "reading is better" frame of reference. But we are also excelling at destroying the planet (as a species we are doing extraordinary "well" at this). At this point, we invoke a battle of frames. What FRAME is a better frame of reference? We haven't a clue. Thus, in my mind such talk is pointless.

      Of course we like to beat our chests and claim that we are "better" or "special." We like to say these things because we are the protagonists to our own life stories, and we thus root for ourselves. But dissing the millions of other species is not something that comes naturally to biologists and others who carefully study the specialness of those other species.

      When we loudly announce that no other species could possibly have built a rocket ship and traveled to the moon, and that we are therefore "better" because of that (amazing) accomplishment, this invokes an implicit frame that these things are the sorts of thing that we were SUPPOSED to do. But for many of us, life does not offer an instruction manual announcing that humans are better, or worse or anything at all. Instead, what we are "supposed to be" is something we feel in our bones. We are amazed and awestruck spectators to the spectacular unfolding of a myriad of life forms, of which we are admittedly one of the most complex. But we are one small branch of a vast inter-connected web of life forms. Why not just accept this for what it is and live one's life among in harmony among our millions of cousins? Why would we need to fret about what species is "better"? In my mind, that is the strange sort of compulsion that makes for beauty pageants and other needless competitions that distract from the magnificence of all that is.

      BTW, I know that some readers will be thinking that thoughts like those that I've written above lead to the living of pointless and immoral lives. I beg to differ.

  18. Dan Klarmann says:

    I though that I'd kicked the How are Humans Better? discussion over to this new post a couple of days ago. Apparently not.

  19. Mark Tiedemann, I believe, correctly corralled my sentiments. Though I like to think that my arguments are non-religious, I must confess; that would be impossible for me to achieve. The concept of "better" comes from my Biblical roots. In Genesis 1:31 this is denoted with the phrase "and it was very good," which is associated with the creation of people and, "and it was good" which is associated with all else. So, God thinks everything is good, and people are very good.

    Please keep in mind; this is from God's perspective, not ours. Christians won't describe people as "good" or "very good." Remember, we're the ones telling you we're all broken.

    I believe the "intersection" if you will, of our different world views lies in the future. We both look forward to a day when people are (again) very good. What causes this transformation is a matter of differing philosophical outlooks. Mine tells me that this transformation will come with help from an external source. Then again, I don't pretend to actually understand it at all.

    I mean this in strictly religious terms. Christians spend hours in Bible studies looking back at people and stories in our Bible saying, "they didn't get it" or "they didn't see it." The New Testament is really just one big “You’re-not-getting-it” from God. How will the future Followers of The Way judge us? Will they announce to their contemporaries that we didn't get it?

  20. Dan Klarmann says:

    Most Christian Bible Study is used to support presumptions rather than to figure out meanings. Any random large text can be deconstructed to support any supposition. The Bible is no exception.

    Those Christians who actually study Biblical exegesis tend to lose their fundamentalism, as they learn that what was actually written often barely resembles what they were raised to believe is the inerrant word.

    I receive any interpretation of exact words in any English Bible with a healthy spoonful of salt. Especially something as vague as a modifier to an adjective (found once) as proof of "better" status.

    But this thread has moved far from the subject: Debunking "irreducible complexity."

    • Erich Vieth says:

      Dan: Your point that those who carefully study Biblical exegesis tend to lose their fundamentalism is well illustrated by the case of Bart Ehrman, who is now a prominent (agnostic) who is nonetheless well-respected for his encyclopedic knowledge of the Bible. When he was younger, he was a Moody Bible College student who believed in innerancy. http://dangerousintersection.org/2006/10/22/who-c

  21. "…those who carefully study Biblical exegesis tend to lose their fundamentalism…" ?? That is a ridiculous statement.

    It seems to me that, when it comes to religion, your intersection has a stoplight stuck on red.

    I guess I'd better move to a new thread.

  22. Richard,

    I think what Erich meant was that when the source material is examined with an open mind and a willingness to accept the evidence thus discovered, it becomes increasingly difficult to hold Biblical (or Koranic or Mormon or etc) texts as somehow inerrantly the Word of God. And since we—or at least I—see fundamentalism as something based on the assertion that it is, literally, the word of God…

    Unless you have a different take on what Fundamentalism is?

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