As a skeptical, irreligious person I must admit that in many ways I am defined by my uncertainty with respect to the consequential and contentious issues. Does God exist? I don’t think so, but I’m not certain. Is there absolute morality? I’d like to think so, but I’m not certain. What are the exact processes of evolution? I understand a great deal about the evolutionary processes that take place, but I’m not certain. How did the universe come into being? Perhaps the physical universe had no beginning and will have no end, but I’m not certain. Is there good and evil? I’m inclined to think this is a humanly contrived dichotomy, but I’m not certain. Does life have meaning? I hope so, but I’m not certain. Can I trust my own thoughts? I believe so, but I’m not certain. By examining the evidence and attempting to evaluate it objectively I have come to a number of conclusions with respect to these consequential and contentious issues, but these are founded on probability, not certainty.
Throughout history religion has served as a means to posit certainty. Psychologically humans are pattern seekers, we observe the world and attempt to construct a framework with which we can assign meaning to what we see and experience within it. When we see the shape of a rabbit on the surface of the Moon it is not because there is actually a rabbit on the Moon it is because of pareidolia, the perception of significance in randomness. Religion is utilized in much the same way, as a framework with which humans can project significance on a universe that appears random. Similarly science serves as a framework for us to try and understand the universe, however religion and science differ on the matter of certainty. Within science even well-documented, widely observed, extensively researched scientific theories, such as gravitation or evolution, that are considered facts are not considered to be absolutely certain. Science is about probability, not certainty.
Within religion humans can find the certainty that science is not willing to offer them. All major religions offer absolute truth primarily through prophetic revelations and sacred texts. When you wonder why you are here, how you got here, and what you should do religion extends an invitation, an invitation to partake in the truth only it can provide. This is an aspect of religion that I find to be both disquieting and objectionable. Religious truths are always questionable, either on historical, scientific, or philosophical grounds, and claims of absolute certainty are a farce to support fideism. Faith is the antithesis of the scientific method and religious certainty can only be maintained through faith. Atheism is not based on the certainty of God’s nonexistence, that would be fideism, but on the improbability of God’s existence based on the evidence. Although I understand why so many need to find solace in religious truths, faith, and a belief in God I myself cannot on evidential and objective grounds. I’m just not certain.
On multiple occasions I have heard the bacterial flagellum (pictured above) used as evidence of irreducible complexity in biology, an argument often used by promoters of intelligent design. After examining this diagram it is not difficult to imagine why promoters of ID would claim it as evidence. The bacterial flagellum is a complex and rigidly organized appendage that superficially appears to be an intricately planned machine rather than an accidental biological structure. And if such an intricate thing looks too complex to be reduced or to have evolved from simpler forms, what other explanation remains except design? However, as with most arguments for intelligent design, evoking irreducible complexity is a fallacious action based on naive conceptions of biology and evolution.
Bacterial organisms have existed on Earth for the past 4 billion years, a very long time for evolutionary processes to be taking place, and have adapted to live in virtually every conceivable environment. Populations of bacteria grow exponentially, with billions of generations produced in a relatively brief period of time, allowing natural selection to have a very strong influence. Evolutionary biologists have theorized that large populations of organisms are more readily influenced by natural selection and that prokaryotes, bacteria and archaea, more readily exchange genes amongst each other. Therefore a large population of prokaryotes evolving over a vast period of time would predictably possess very intricate and complex biological structures. The bacterial flagellum is no surprise or dilemma for evolutionary biologists, in fact it is expected.
Utilization of the bacterial flagellum, or any other so-called irreducibly complex biological structure, as evidence of design is itself an evidence, evidence of a clear misunderstanding of biology and ignorance of evolutionary processes. Anyone who would challenge the modern theory of evolution with intelligent design either does not understand the widely accepted, peer reviewed science they are challenging or has been blinded by their religious convictions. After all ID is a religious view, not a scientific theory, supported almost exclusively by Christians, not scientists. Irreducible complexity is just one in a long line of fallacies promoted by the ID camp that poses no serious challenge to legitimate science.
Intelligent design and its supposed evidences are intellectually dangerous because they provide the public a falsified view of biology and evolution and the religious an erroneous vindication in denying the prevailing views of science. None of the discoveries in the fields of evolutionary biology, genetics, paleontology, etc have done anything except substantiate the accidental, impersonal, material processes of evolution as the best explanation for the origin and development of life. Irreducible complexity is a product of scientific illiteracy and religious conviction, not good science, and denying the true origins of astounding, beautifully complex biological structures like the bacterial flagellum only diminishes those astounding and beautiful qualities.