" You're making a circular argument. The evidence is objective, and it can even be objectively tested on a repeated basis."
No, I am saying we have no way to know if the evidence is objective until it is tested. Basic epistemology.
"But the inferences and conclusions made by the observer on the basis of those tests depends upon the biases and assumptions of the observer."
No, exactly wrong. It depends on the objective evidence that is gathered.
"This is nonsense."
Yes, it IS nonsense. That anybody would think that subjectivity is the basis of all knowledge claims is illogical. Yet, you do.
BS. I have objective evidence that you exist right before my eyes. It is self-evident, and it does not have to be "tested" first to be objective.
That anybody would think that subjectivity is the basis of all knowledge claims is illogical.
It is not "illogical." It is a simple statement that may be true or false; reasonable or unreasonable. In this case it is unreasonable, and for that reason I have not made such a statement. I have never believed subjectivity to be the "basis of all knowledge." I have claimed, and continue to maintain, that science cannot entirely divest itself of subjectivity any more than it can entirely divest itself of human observers.