Claim CF011:
Genetic algorithms are claimed to demonstrate that evolutionary processes can create design, but in such algorithms, the design is smuggled in in the form of the fitness function. Evolutionary algorithms do not create specified complexity.Source:
Dembski, William A., 1999. Why evolutionary algorithms cannot generate
specified complexity. Metaviews 152 (Nov. 1). (www.meta-list.org).
http://www.leaderu.com/offices/dembski/docs/bd-algorithms.html
Response:
- The fitness function of genetic algorithms need not include any new
information. A fitness function can be expressed as whether the
algorithm performs better or worse in a particular environment. The
only information is provided by the environment, which is usually
modeled on the real world. The claim makes sense only if design is
defined as what is in nature already.
One may argue that nature and design are inseparable (and Dembski seems to make just such an argument; Dembski 2002, xiv), but this invalidates the design argument. Design only has meaning if contrasted with nondesign, and defining design as all of nature makes nondesign nonexistent. - Genetic algorithms often come up with novel solutions which sometimes
even surpass direct human designs (Koza et al. 2003) and which do not
rely on human expertise (Chellapilla and Fogel 2001). Humans may have
told the algorithms what to do, but it is the how that defines the
design.
- Genetic algorithms are not perfect evolutionary simulations in that they have a predefined goal which is used to compute fitness. They demonstrate the power of random variation, recombination, and selection to produce novel solutions to problems, but they are not a full simulation of evolution (and are not intended to be). In simulations of biological evolution, fitness is evaluated only locally; survival and reproduction is based only on information about local conditions, not on ultimate goals. However, the simulations demonstrate that distant fitness peaks will be reached if there are conditions of intermediate fitness (Lenski et al. 2003). Evolutionary processes do not "search." They respond to local fitness topography only. The fact that evolution (occasionally) reaches fitness peaks is a by-product of evolving on correlated fitness landscapes using purely local fitness evaluation, not an intended outcome.
Links:
Marczyk, Adam, 2004. Genetic algorithms and evolutionary computation. http://www.talkorigins.org/faqs/genalg/genalg.htmlRBH. 2003. Untitled. (5 July). http://www.iscid.org/boards/ubb-get_topic-f-6-t-000384.html#000013
References:
- Chellapilla, K. and D. B. Fogel, 2001. Evolving an expert checkers playing program without using human expertise. IEEE Transactions on Evolutionary Computation 5: 422-428. http://www.natural-selection.com/Library/2001/IEEE-TEVC.pdf
- Dembski, William A., 2002. No Free Lunch, Lanham, MD: Rowman & Littlefield.
- Koza, John R., Martin A. Keane and Matthew J. Streeter, 2003. Evolving inventions. Scientific American 288(2) (Feb.): 52-59.
- Lenski, R. E., C. Ofria, R. T. Pennock and C. Adami, 2003. The evolutionary origin of complex features. Nature 423: 139-144. http://myxo.css.msu.edu/papers/nature2003/ See also: National Science Foundation, 2003. Artificial life experiments show how complex functions can evolve. http://www.sciencedaily.com/releases/2003/05/030508075843.htm
created 2003-4-14, modified 2005-7-31