Irreducible Complexity and Relative Irreducible Complexity: Foundations and Applications

The concept of irreducible complexity is a great intuitive concept which has historically lacked a well-defined theoretical basis. This paper will show how computational theory gives an adequate account for what irreducible complexity is, what irreducible complexity’s possible biological implications are, and how irreducible complexity can be useful to molecular biologists and creation biologists. www.creationbiology.org 1 1. Irreducible Complexity Basics and History 1.1 What is Irreducible Complexity? Many teleologicallyoriented biologists have long viewed biology in a holistic manner. That is, they view the whole of a biological system as having priority over any of its parts. That is, the parts are important, but only as contributors to the whole. The concept of irreducible complexity (IC) is an attempt to capture holistic thinking into a framework which is amenable for scientific understanding. The term “irreducible complexity” was introduced in 1996 by Michael Behe in the book Darwin’s Black Box. In this book Behe argued that some biological systems are Irreducibly Complex. Behe (1996, p. 39) defined irreducible complexity as follows: By irreducibly complex I mean a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning. An irreducibly complex system cannot be produced directly (that is, by continuously improving the initial function, which continues to work by the same mechanism) by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional. In Behe’s definition of IC, Behe defines a holistic entity as a group of parts which are nonfunctional except in the context of other parts, and only by working together do these parts achieve function. Thus, the empirical test for this type of holism is whether or not removing a part causes the function to cease. This certainly doesn’t capture all types of holistic systems, but it is clear to see how IC relates to a holistic view of biology. 1.2 Irreducible Complexity Before Behe. Long before Behe, creationists and other teleologically-oriented biologists made similar claims about biological holism, though in much more general and intuitive forms. The essence of the argument is that many biological systems act holistically, and therefore their development must have taken place in a holistic manner, whether through direct design or some other mechanism that operates holistically. We will refer to all of the arguments which take this form as being instances of irreducible complexity, even though such terminology is anachronistic for the examples discussed. The claims of irreducible complexity were being made even before Darwin. In Animal Kingdom, Cuvier (1834, p. 7) wrote: Organisation, then, results from a great variety of arrangements, which are all conditions of life; and it is easy to conceive, that if its effect be to alter either of these conditions, so as to arrest even one of the partial motions of which it is composed, the general movement of life must cease. .... Life, then, in general, presupposes organisation in general; and the life proper to each individual being, presupposes an organisation peculiar to that being, just as the movement of a clock presupposes the clock itself; accordingly we behold life only in beings that are organised and formed to enjoy it, and all the efforts of philosophy have never been able to discover matter in the act of organisation, neither of itself, nor by (pg 8) any external cause. What Cuvier was saying was that the organization of parts is greater than the motion of any individual piece, and that, without the unit of organization (which, for Cuvier, was the organism), the pieces tend to run counter to the mode needed for life. Cuvier viewed the organization of organisms holistically, and, for him, the organization itself was a species, with the possible variations on that organization being varieties. Behe’s concept of irreducible complexity focuses on much smaller subsystems of organisms, and treats them independently. However, the basic form of the idea remains the same. The parts require the organization of the parts to perform a task. Without the organization (which, for Behe, is a system which performs