paxx,
I'm an orc
The concept of proof is different on a practical or scientific level and on a philosophical level.
There may be a valid philosophical point about the categorical existence of proof as an absolute quality, but that isn't necessary to establish a reasonable level of effective proof.
While one can make the argument that if I have not duplicated the entire effort of some other person, then my acceptance of the results they reach constitutes a matter of faith. This may be literally true, in that I have confidence in the system under which the results were obtained. From a practical basis, whether I have actually undertaken the effort to duplicate the process leading up to the results, the important point is that I could do so, and that others *have* done so. That is the value of the system in which those results are obtained.
There is an immense practical value in the concept of proof. There is nothing about the concept of proof that, in and of itself, is invalidated by the idea that it can be philosophically categorized as ephemeral.
Often, the veracity of the concept of proof is challenged by those who cannot produce proof for their particular worldview or desire, and who therefore attempt to hold the whole concept of proof in question as a means of obtaining some validity for their ideas.
For example, I can prove that electromagnetic fields exist, both from a logical analysis of the phenomena, and from the fact that those fields are applied to objects that have a very real, everyday existence.
The avenue of proof does become somewhat more arguable when applied to events where there is some evidence to examine, but little or no other context in which to examine that evidence, except the suppositions based on other knowledge of similar context.
Evolution and anthropology *do* fall into that category, in that we have a body of evidence, but the determination of what that evidence means is subject to speculation and extrapolation of our current understanding of the context in which they exist (and are found). The thing is, no reputable scientist will categorize that framework as 'proof'. I can, as a scientist, prove that a computer, for example, exists, and that it is made possible due to an underlying framework of electromagnetic physics and logic. And therefore, by extension, we can 'prove' that the framework itself exists.
I cannot, however, prove that natural selection is the mechanism that fully explains the evidence that supports the concept of evolution. That's why it's a theory, rather than an axiom or a proof.
However, from a scientific standpoint, the evidence for the above is sufficiently strong to provide a functional framework for study, and a meaningful explanation for the course of events. It may not be declarative proof, but in the same fashion that the existence of computers (for example) establishes the correctness of our framework for electromagnetic theory, the benefits that we accrue in terms of genetic study and understanding of life establishes that the scientific theory of evolution is a useful theory that can be applied with concrete results. That may not be philosophical proof, but it is practical proof.
If it turns out that our framework is incomplete, we will adapt it to suit. But that doesn't mean that the framework is useless, even if we adapt it later.
To provide another example, Einstein's theories of special and general relativity subsume Newton's laws of motion and gravitation. That does not mean that Newton's laws are useless, as they are quite accurate in the vast majority of cases that we examine, it is only in the extreme reaches of motion and gravitation that Newton fails and Einstein is then needed.
