The methodology of science limits itself to considering only natural
causes. This rules out the possibility of design as a cause, even though
inferring design, consistent with scientific methods, is logically based
on data observed in nature.
The claim is obviously false, because science can and does detect
design in several contexts, such as archaeology and forensics. Design
theorists themselves point to such examples as evidence that design can
be detected (Dembski 2002). Considering intelligent design besides
human design, though, is ruled out by the fact that proponents say
nothing positive about what such intelligent design implies.
Science does not limit itself to considering only natural causes.
There have been numerous scientific investigations of phenomena which
presumably do not have natural causes, such as the power of prayer
(Astin et al. 2000; Cha et al. 2001; but see Flamm 2004, 2005; Krucoff
et al. 2005), divination (Enright 1999; Randi 1982), and life after
death (Schwartz et al. 2001). What matters to science is not that
something be natural (whatever that means), but that observations can
be objectively and reliably verified by others.
Astin, J. A., E. Harkness and E. Ernst. 2000.
The efficacy of "distant healing": a systematic review of randomized
trials. Annals of Internal Medicine 132(11): 903-910.
Cha, K. Y., D. P. Wirth, and R. A. Lobo. 2001. Does prayer influence
the success of in vitro fertilization-embryo transfer? Report of a
masked, randomized trial. Journal of Reproductive Medicine 46:
781-787. http://www.jreprodmed.com/abs/jrm1137.htm
Enright, J. T. 1999. Testing dowsing: The failure of the Munich
experiments. Skeptical Inquirer 23(1): 39-46.
Flamm, Bruce. 2004. The Columbia University "miracle" study: Flawed
and fraud. Skeptical Inquirer 28(5): 25-31.
Flamm, Bruce. 2005. The bizarre Columbia University "miracle" saga
continues. Skeptical Inquirer 29(2): 52-53.
Krucoff, Mitchell W. et al. 2005. Music, imagery, touch, and prayer as
adjuncts to interventional cardiac care: the Monitoring and
Actualisation of Noetic Trainings (MANTRA) II randomised study.
Lancet 366: 211-217. http://home.infostations.net/srm/3204A.pdf
Schwartz, Gary E. R., Linda G. S. Russek, Lonnie A. Nelson and
Christopher Barentsen. 2001. Accuracy and replicability of anomalous
after-death communication across highly skilled mediums. Journal of
the Society for Psychical Research 65(862): 1-25.
Wiseman, R., J. Beloff and R. L. Morris. 1996. Testing the ESP claims
of SORRAT. Skeptical Inquirer 20(5): 45-46,61.