I don't feel the need to convince them it can. It is just a matter of fact that it can. Objective as far as we know to the best of our ability is completely in reach. You can test plenty of things you don't objectively witness at a casual glance. Air, gravity, etc. None of those involve miracles, none of them involve faith. There are some that yes, believe everything is subjective, and that nothing externally is real. But that is just as unfalsifiable as a claim to the contrary. It is best when dealing in reality where you have to work within the parameters it requires to best understand it on it's terms, and assume that it is at least as real as it is going to get this time around.