It does no good to try to invalidate logic. Logic is the process of non-contradictory identification. Despite what modern philosophy asserts, it is not the process of arbitrarily making up connections between things.
In the context of science, we use logic to analyse the evidence of our senses and identify which facts of reality that implies. And what those implications imply and what those imply and so forth.
Building up and sideways as we identify more and more facts of reality. And integrating what we observe with what we can deduce in an ever-tightening spiral.
Why then do people deny that some science is settled? People do, including many alleged champions of science and reason.
This is largely due to the philosophical influence of philosophers like Hume. Hume and others like to attack the validity of certainty.
Hume’s epistemology goes much like this:
By this means all knowledge degenerates into probability; and this probability is greater or less, according to our experience of the veracity or deceitfulness of our understanding, and according to the simplicity or intricacy of the question.David Hume, A Treatise of Human Nature, Book 1, Part 4, Section 1
Want more proof that Hume is against certainty? Well, here you go. Here he attacks the process of induction by trying to assert it is baseless to infer anything about the future from the past!
For all inferences from experience suppose, as their foundation, that the future will resemble the past, and that similar powers will be conjoined with similar sensible qualities. If there be any suspicion that the course of nature may change, and that the past may be no rule for the future. All experience becomes useless and can give rise to no inference or conclusion.
It is impossible, therefore, that any arguments from experience can prove this resemblance of the past to the future, since all these arguments are founded on the supposition of that resemblance. Let the course of things be allowed hitherto ever so regular; that alone, without some new argument or inference, proves not that, for the future, it will continue so. In vain do you pretend to have learned the nature of bodies from your past experience.David Hume, An Enquiry Concerning Human Understanding, Cause and Effect, Part I
As we see, Hume believed that what is true today might not be true tomorrow!
Now, if you put it this way, people might think you are talking nonsense. They are unlikely to think that the nature of reality changes from one day to another!
This kind of philosophy still influences people. They believe that we cannot be certain about anything. This kind of philosophy has led them to think that the human mind is just too fallible to be sure that the human mind can grasp the truth.
Kant reinforced this by trying to assert that we do not observe things as they are but only as they appear to our senses.
The result of this is an implicit distrust of our senses and the belief that what we observe can always be akin to an illusion!
If we cannot even be sure about the evidence of our senses, then what reason do we have to be certain about anything? None, you have no reason to be certain about anything, if you accept this baseless premise.
However, this is baseless. We do have reasons to be certain about some theories. Theories that we can prove to be true based on the facts of reality.
Just because you want to assert that “we might know better tomorrow”, does not mean that we cannot be certain today. Not if we understand where the evidence points. Especially when it comes to theories we know for a fact must be true, without any possibility of it being otherwise.
Just because you can imagine an alternative to irrefutable facts, is no reason to entertain that it is a possible alternative.
Your ability to imagine that something is true does not make it a possibility.
If something is truly settled, that means that if it were not true, it would contradict the facts of reality. But contradictions do not exist. Therefore, it would be absurd to assume that settled science is anything but settled!
Even if you do not understand that some theories are settled beyond any reasonable doubt, they are still settled. Even if you want to pretend that reality is not what it is and that there is any possibility that it could be otherwise.
If you want to pretend that irrefutable facts are not what they are and that reality is not what we know it is, that is your business. It is very scientific to accept that some science is settled. It is unscientific to assert that it is not.
To wrap up, here is a bonus picture of a manganese atom. You know, the existence of which some people think is still not settled…