Is Scientific Knowledge Provisional?
Usually science minded adherents can be divided into two prominent camps. First there are the realists, who hold that mathematical theories can provide direct insight into the nature of reality, and secondly there are the instrumentalists, who believe that theory provides a means for predicting what our measuring devices should register but tells us nothing about any supposed underlying reality. I personally side with the realist camp, but regardless, the debate as to the value of science and what it can ultimately do for us rages on.
Recently I have heard several objections to the notion that scientific knowledge can only be provisional, but I think this notion arises from the mysterious way in which science works against our intuition. To clarify this point we could say, with regard to scientific knowledge, the distinction which needs to be made is when considering the status of our current understanding prior to new discovery and after discovery.
Thus, it seems to me, that any information which has not yet been discovered or exists theoretically (i.e., remains unverified) denotes a level of uncertainty, and so is provisional. Whereas any information which has been discovered and tested (i.e., verified) denotes an established understanding–-the basis for our scientifically gained knowledge.
Needless to say, it would be remiss not to point out that post-discovery scientific knowledge carries with it a tentative certainty-–and by this I mean the established knowledge may be incomplete and/or subject to revision (e.g., the Big Bang theory is incomplete, but so far as we know accurate, and other theories may later be improved upon, such as cardiovascular understanding which was greatly improved with the advent of MRI technology).
What this suggests is that, because our certainty is tentative, absolute knowledge may be out of our reach even as we feel absolutely confident, or certain, of the knowledge we do have. Additionally, modern cognitive science also reveals that our certitude is an emotional construct, and in actuality, there is no such thing as absolute certainty--especially when we know the brain so often perceives the world incorrectly and that our intuitions are usually off by a wide margin.
Of course I am familiar with the common objection: But we know for certain how some things work (absolutely). Take microwave ovens for example. We know exactly how a microwave oven works. We can explain every detail as to what makes it work and, furthermore, can give lengthy explanations on how it works. Our knowledge of microwave ovens, then, seems to be absolute. We even know about electromagnetism and how microwaves function, so it's not a big mystery of why a bag of Orville Redenbacher popcorn pops when you microwave it. And I'd agree, our understand with regard to microwave ovens and microwave popcorn is as absolute as it is going to get.
But let's not overlook the fact that this is only because it is an understanding which we were able to derive from prior discoveries in physics, discoveries which were, and may still be, subject to revision, refinement, and/or improvement. So the fact that our certainty rests on a foundation of ongoing research suggests there is a certain amount of uncertainty we must predict, even expect, as any future find may change our minds about the basic understanding of microwaves, even as this does not jeopardize our current understanding of how microwave ovens and microwave popcorn work, per se.
So although it is true there are both logical and scientific claims we can deem absolute, our understanding never starts out that way. We begin with uncertainty and then work our way toward certainty--which is basically saying we move from ignorance to understanding--and science it the tool which helps us do this. So anything which is absolute is only deemed "absolute" because of the prior provisionality which allowed us to test the competing options and then either falsify or prove them, and after which we gain further insights--thus adding to the certitude in our scientific knowledge. Even so, I would caution, since science has, traditionally speaking, had a way of surprising us with rewriting our understanding of the world (e.g., quantum mechanics being a fitting example), we cannot be sure, at least not a hundred percent anyway, that tomorrow a new discovery won't have us updating the details of our current understanding and causing us to rewrite our textbooks on what we thought we knew.
Anyway, that's the gist regarding the provisionality of scientific knowledge.