Good response.
Nice of you to snip the context of my reply. Behe said 'purposeful'. How do you determine purpose without knowing intent?
"Do you think it is possible to infer a general purpose without knowing the specific intent? In the movie, Contact, a signal representing a long sequence of prime numbers is received. Do the characters in the movie know anything about the intelligence's purposes or motives for sending the prime numbers?
Yes they do. They know that it is intended to be a communication. This is a movie remember, without recognizable signals there would be no plot. We assume that counting systems will be universal so primes will be recognizable by any intelligence that uses math. Is this necessarily the case? Are there counting systems which have different primes? Is it possible that there are aliens that ignore primes?
However the entire thrust of ID as presented by DI is based on biology. Where are the easily recognized universal signs in biology?
"Do they know anything about the technology employed or about the intelligence's physical makeup? No. Yet, the signals exhibit hallmarks of intelligence. How so, since the intelligence's intent is not known?
What are the hallmarks of intelligence? The only model we have for intelligence is ourselves, the only products of intelligence we have for comparison purposes are ours.
IDists claim we identify design by assuming that certain levels of complexity cannot occur naturally.
"If by 'naturally' you mean by operation of 1) a law, or 2) chance, as opposed to 3) the action of intelligent agency, then yes, I agree. There are three possible causes for things: chance, law or design.
Are the three mutually exclusive? If not, how does Dembski's filter identify fusions of one or more.
We assume complexity as an attribute of design because humans can and do create complex objects, however that complexity is not how we normally identify a designed object. When we examine an artifact we ask ourselves 'how does it resemble other objects we know are designed (by humans)', 'does it have any attributes that result from its manufacture method(tool marks)', 'what can it be used for, why was it made'. All questions we ask about the object centre around what we already know about human design, not about design that non-human intelligences could possibly make.
"Why should one except in the first place this Humean inductive framework of all our knowledge of the world as an extrapolation from past experience, much less for how design is recognized in the first place? If we purport to attribute design on the basis of induction, we have already presupposed the ability to identify design independently of induction because as Hume says, unless you know it by experience, you know nothing of it. And if that were the case you could never know it at all.
I'm not Hume.
"We do not perceive intelligence directly, but by its signs. And though signs of intelligence can be learned and confirmed by experience, our ability to recognize them cannot originate in experience. The same goes for recognizing "intent".
Ok, then how do we recognize design? Give me an example.
ID, by its very nature, will produce false positives and false negatives as often as it will be correct.
"If that proved to be true then the theory would turn out to be useless. I think the jury is still out on whether there is a reliable criterion for detecting (not eliminating) design. False negatives, though an inherent problem with eliminating intelligent causes (because of their innovatioan and unpredictabilty, etc) are not much of a problem for science in general right now, which doesn't presume anything as being designed anyway. If there is a rigourous mathematical method of applying the probability criterion to cases then false positives will be minimized. Either way, nothing in ID theory stops anyone from looking for causes of chance or necessity
Ok, then how do we recognize design? Give me an example.In a scientific methodology, first would be the observations that intelligent agency is known to produce complex specified information. Where complex specified information exists from known causes it is always the result of intelligent agency, and never the result of chance or necessity. The hypothesis would be that if objects were designed they will contain complex specified information. Experimentally, biological structures could be examined and reverse-engineered to see if they exhibit CS. If some machine-like structure in microbiology has a particular arrangement of parts which is necessary for those parts to function, and if it has a vastly improbable arrangement of many interacting parts, a tentative conclusion of design is warranted because such attributes are known to be produced by intelligent agency and because there is no other known mechanism that is causually sufficient to produce such IC biological structures.
The devil is in the details, though, and if becomes a matter of how to quantify mathematically the information content of a biological structure. I do not know enough about statistical mathematics to be able to answer the question, but I assume there are biologists and mathematicians who could do this in a rigorous way. I would like to see such experimentation on something like this:
The F1-ATPase enzyme has a tiny structure 10x10x8 nm that is analogous to an engine block, and a drive shaft. It rotates at 30 to 240 rpm. The "block" is based on a triangular arrangement of three subunits.
Hiroyuki Noji, Ryohei Yasuda, Masasuke Yoshida, and Kazukiko Kinosita Jr., "Direct Observation of the Rotation of F1-ATPase", Nature 386 (Mar. 1997), pp. 299-302. Separately there are a diagram and four ".mov" files (400 to 1700 KB) available.
Cordially,