Thank you exchemist. Let me answer in two parts.
Firstly, in each of Matthews posts he made it clear, from the outset, that he was not talking about ID as promoted by the Discovery Institute. I felt I had highlighted this in my questioning of Fraggle Rock's post. I share your distaste for the 'work' of the Discovery Institute. I felt that you - and possibly Origin and Daecon too - appeared to have allowed that distaste to produce an emotional response to the very mention of intelligent design, rather than a calm consideration of what Matthew was saying. I am happy to have a conversation around the topic, as long as we agree - as you have done - that this has nothing to do with religion.
When I first visited this forum, or it may have been another one (I've been away for ages!) I seem to recall a member arguing that there was a difference between Intelligent Design and intelligent design. He wanted to restrict the former to the fundamentalist, religious view and the latter (in lower case) to the possibility of some type of intervention by some completely natural agency. That seems to me a useful distinction.
Now, before I answer your question a couple of clarifications. Firstly, I have no idea what Matthews ideas about intelligent design are, other than his clearly stated view that is has nothing to do with the supernatural. Secondly, I have no set view on the likelihood of there being any form of intelligent design, I just find the possibility interesting.
So, to the discussion. You state "I would still contend that anyone who posits artificial intervention by an outside agent in the natural working of earthly biology - if that is what you mean by ID - needs evidence for this hypothesis."
I am not at the stage of positing such intervention. I am asking a more basic question. "If such intervention had occurred, would we be able to recognize it and by what means?" Research on the mechanisms and paths of evolution are ongoing. There is much that we have yet to discover. I imagine, a century from now, we would be astounded by the level of detail we have achieved. And in that world, probably, there will not even a hint of intelligent design.
However, two points - such intervention is, in my view imminently plausible and if it did occur, would be of enormous significance. And, if we don't look for it, our chances of finding evidence for it is greatly diminished.
You then ask what is, for me, the key question: ".... what evidence do you think there could be - i.e. what research programme could be envisaged to detect it - for such a thing?"
That is exactly the point I am at. How might we go about investigating the possibility? I don't know. It is not something I have given a lot of thought to, but I don't think the possibility should be rejected out of hand, especially through the strawman of attaching intelligent design to religion.
I hope that makes my position on this clear. I'll be happy to address any points, or questions you have.
Yes, thank you, I think I understand your position.
This question, of how one could reliably detect "design" in nature first arose from the famous watchmaker analogy by William Paley, a c.18th Anglican clergyman and academic thinker, that the intricate complexity of nature was evidence of (in his argument, God's )design. "Suppose I had found a watch upon the ground….."etc. Most scientists and philosophers that have considered this issue have concluded that there is NO means of detecting "design" unambiguously. The reasoning, as I recall, goes something like this.
1) To detect "design", one would have to see something that was definitely "not natural", in other words, something that
could not have arisen by the operation of natural processes.
2) But science has, throughout its history, repeatedly discovered complex things, or processes, for which there was no known natural explanation at the time of discovery - and then, as time goes by, natural mechanisms have been found for them.
3) So by what possible criterion could one identify something in nature for which one could be confident that
no natural explanation would
ever be found in future, as science progresses?
4) The evidence of history is that there seem to be
no such criteria. Any attempts at defining such criteria would - if believed - merely have the effect of stopping research into the topic, i.e. of stopping science, on what would be an essentially arbitrary basis.
At this point it may be worth pausing to consider what science is. "Scientia" means simply "knowledge". What the modern world calls "science" is really short for "natural science", the knowledge of
natural things and processes. It is a search for
natural explanations of phenomena in the physical world around us. As soon as one postulates design in relation to a phenomenon, one is in effect claiming there is an "un-natural" or"super - natural" process at work.
The above is, I believe, is the real reason why so-called "intelligent design" gets short shrift in the science community. I could summarise it as follows:
1) Design can't be defined, so no test for it can be constructed, so it cannot be a scientific approach to the world.
2) Worse, alleging design has the effect of chilling the search for natural explanations, i.e. stopping science itself.