Then the natural sciences should admit the possibility that the origin of life and the origin of the species may be beyond their scope.
Sure it is. You don't get consensus otherwise, and that's what you've got.
Consensus cannot be compelled and that is what the promoters of natural evolution are trying to do. Every scientific theory which has been overturned has first been attacked by a minority, if not by a lone individual. Proper science should not be "I am right now shut up," but rather "let the debate begin." If the evidence for natural evolution is so compelling, why are you afraid of an open debate.
There is a workable mechanism, of course - natural selection is the mechanism which drives evolution.
Again we need to make a distinction, this time between micro-evolution (within one species) and macro-evolution (the formation of a new species). No one will dispute the process of micro-evolution, either natural or through artificial breeding. The various breeds of dogs is proof of that. But in the end, no matter how much you breed dogs, you will always end up with a dog.
The problem is when you take these observations and try to use them to explain macro-evolution. There has yet to be shown a mechanism that will explain how random genetic mutations will produce a new species. This become especially apparent when some of the mutation require multiple and simultaneous genetic mutations or when the intermediate forms are useless and do not enhance an organisms chances of survival.
I really don't think it's too much to ask that scientific theories are, well, scientific.
Part of the problem is that the natural sciences have appropriated to themselves the term scientific. The natural sciences are only a part of the knowledge of man. When the limits of the natural sciences have been met they need to be accompanied by the other areas of human knowledge. The natural sciences need to rediscover the humility to say "we do not know." This does not mean that they should stop trying to discover natural explanations but that they should not presume that there must be one.
Theories that invoke such things can be lots of things, but science isn't one of them. Sorry.
Such theories that go beyond what the natural sciences can properly explain (such as at present the origin of life and the origin of the species) are also not science. The statement that "there must be a natural explanation" is not scientific but only a creedal statement of belief.
Perhaps you have some affirmative evidence - i.e., something beyond "you can't disprove it!" - to bring to the table for such a thing?
Take as much time as you like ;)
Consensus cannot be compelled and that is what the promoters of natural evolution are trying to do.
You have the wrong sort of consensus in mind - not consensus among the public, but among professional scientists, where the question of evolution has long been settled. Sorry again, but there it is - creationism is not considered a serious alternative among scientists.
Proper science should not be "I am right now shut up," but rather "let the debate begin."
You're rather late to the party. As much as I hate to say it, that debate has begun, occurred, and ended among scientists. ID brings nothing new at all to the table, and so there's precious little reason to pretend it's a live controversy - among scientists, it isn't, the school boards of the country notwithstanding.
Again we need to make a distinction, this time between micro-evolution (within one species) and macro-evolution (the formation of a new species).
We don't need to do any such thing - that distinction is a wholly artificial construct invented not by scientists and evolutionary biologists, but by creationists who have retreated from the castle walls and into the keep. There is absolutely no dividing line between "microevolution" and "macroevolution" - in fact, those terms are not generally used by professional evolutionary biologists - except for the timeframe involved, and, not to be cynical, in the convenience factor for creationists. When denying the obvious becomes untenable, it is labeled "microevolution", and "nobody denies that". When the supposed immutability of species looks to be in danger, it is labeled "macroevolution" and denied with great vigor.
Part of the problem is that the natural sciences have appropriated to themselves the term scientific.
So basically, you want to join the club called "science", but you don't want to follow the rules set out for members. And who are you?
The natural sciences need to rediscover the humility to say "we do not know."
I see that all the time. In fact, it's by exploring the areas where the answer is currently "I (we) don't know" that glory is gained in science - you can't do that if you don't admit what you don't know, and so there is a very strong disincentive to pretend that everything is known and understood.
This does not mean that they should stop trying to discover natural explanations but that they should not presume that there must be one.
Really, now - there is no presumption that there must be a natural explanation, only that natural explanations are what science concerns itself with. I'm not sure how I can say it any other way, and since this is the third time I've said it, I'm not sure that this is leading anywhere productive.