This statement is not hypothetical, it is a known fact.
This may be the logical and psychological heart of the matter of why you don’t find naive empiricism satisfying. The statement about thrust
is hypothetical (if you (name removed by moderator)ut a value for x) - as indeed is all scientific knowledge - which you would point out in a heartbeat if anyone tried to argue that science could offer us certain knowledge of anything. It just happens to be well-evidenced empirically that a certain rocket requires a certain amount of thrust, backed up by explanations which are just as empirically contingent - about gravity, aerodynamics etc etc. Inductive reasoning does not provide for certainty, but we can make and live by empirical hypotheses very well, which is why some hypotheses are treated as ‘fact’. Therefore, just because naive empiricism is a hypothesis does not mean that it is necessarily unsatisfying, doubtful or weak. Also, given that we cannot hope for what is illogical (certainty from induction), we ought to be satisfied with only having reason to believe proposition 1 was true.
If you accept that number 1 was not dogmatic but hypothetical, you have to accept the same of number 2, because they are formulated in the same way. Therefore, what is entailed is that the assertion requiring empirical evidence for everything
must have empirical evidence for itself, else we have no reason to believe it. Just like the first assertion about thrust must have evidence for itself else we’ll remain unconvinced. The 2nd proposition either
might be able to gain this, or it
might not - it is not a logical contradiction, because there is the possibility that it supports itself in the same way that all knowledge is supposed to. There is nothing to say at the outset that this is impossible, so if you are with me thus far, you have to drop the idea that it is automatically self-contradictory.
But don’t worry, all that means is that you are subjecting the hypothesis of empiricism to the test of evidence, which we should focus on.
You asserted that “experience is required for knowledge”. This proposition does not mention truth, or define knowledge, or talk about evidence.
As a side point, I had given up trying to elaborate the meanings of these because you have a trusty dictionary which is apparently able to read our minds and offer you the ‘real answer’, demoting my argumentation to the status of ‘non-standard terminology’. However, as an example of why dictionaries do not give automatic reason to believe their contents are true, we can see that common sense or some ‘standard definition’ might say that knowledge is having certain belief, when it can be argued that this is impossible.