The claim would be that we observe certain regularities in the way natural phenomena occur ─ that objects fall to earth, that they accelerate as they do so, that the rate of fall doesn't vary with the mass of the object, but varies with eg air resistance; and that for non-relativistic measurements Newton's
F = G (m1m2/r^2)
fits our observations.
The claim would further be that these conclusions are the result of scientific method, hence derived by empiricism and induction hence are tentative, subject to any counterexample we may discover tomorrow or never discover.
What do you say is going on instead? That our observations are wrong, the product of ... what?
Surely the observation, 'Yes, that works' as we land a rover on Mars, has some persuasive value?
To say that there are no such regularities, eg that there is no economy of energy in the interactions of chemistry and biochemistry, so that RNA produces DNA only by a series of extraordinary coincidences, would defy common sense as well as experience, would it not?
No, they're more sophisticated than our primary experience, otherwise we, like the ancients, would still believe the earth was flat and the celestial bodies went round it.
While we still have kinds of scientific determinism, they're no longer clockwork, since our present understanding of QM includes what in terms of classical physics are truly random events, unable in principle to be described in terms of cause&effect, and only describable statistically.
Even the chaos is subject to observable regularities of behavior, which we can fashion into rules of physics.