This sentence is really confused. IF it is scientific knowledge, then it has been justified within that system. So you are being redundant. Another sloppiness is you are using the term JTB which is from philosophy as if it is used in science AND as if it is one thing. It is not used by scientists, the term is not, AND it is not one thing. JTB is a suggestion for how one conceives of knowledge. It is not a methodology, it is not a set of specific criteria. It is an idea inside philosophy and philosophical discussions about how one can and some believe should think about knowledge. Since JTB does not specfic what kind of justification, we know that we are a high level of abstraction. It is not something to be confused with the scientific method, though the scientific method could be argued to be a kind of JTB. The problem with saying that the scientific method is JTB is that science is wary of using T (truth).
But it has changed. I also think it is a poor phrase and you should define it. Generally empirically either means through experience or experiment. Of course this changes over time. We may experience things and have, in science, and also outside, that were not experiences before. Technological advances increase what can be experimented and what can be experienced. So with any common use of the word empirically you are demonstrably incorrect here.
hypothesis or speculation? That, even in science, can be ANYTHING AT ALL.
Right, and since we now know there are ‘things’ confirmed by science that we did not know earlier in time, empirically possible changes.
A square is not empirically possible since it is made up of two dimensional components. It is a non-existent abstraction. I get what you are trying to say but it shows you are confusing two realms 1) math and the empirical world 2) particles that are also waves should have been self contradictory, but it turns out their are not. Particles - like a single electron, can interfere with themselves as if they are waves. The wave particle duality WAS TREATED JUST LIKE YOU ARE SAYING SQUARING THE CIRCLE WAS, until experimentation, the slit experiments, showed it was not only possible it was the case.
So your example here 1) shows me you don’t really get what empirical means since you bring in squared circle which is abstractions has to do with deduction not empirical research, but further you seem to have no idea that things that scientific models would have once ruled out as self-contradictory HAVE TURNED OUT TO BE THE CASE.
You have a non-historical view of science and this leads to all sorts of confusions.