I fully agree, not sure why you think otherwise of me. But we’re not discussing science now but philosophy, the nature and structure of reason and knowledge.
Not all assertions are scientific assertions, logic and reason precede science. Mathematical arguments and proofs for example are nothing to do with science.
So defending some proposition simply requires the clear statement of initial premises and then a sequence of logical steps from them. If you’re arguing that only scientifically defensible propositions are valid then we’re going to disagree I think because I a not an empiricist.