You wrote: "We know what gravity is. We just haven't found the mechanism for it yet."
Actually, gravity is a mental construct. It is what NLP refers to as a process-structure transformation (read distortion). In essence, "Gravity" is a shorthand word that we use to describe the relational interaction patterns between objects based on relative mass. And you are correct, no intervening, explanatory mechanism has been proven to cause the pseudo-thing we call gravity as if it has some independent existence.
Those who have forgotten the Sapir-Whorf hypothesis will dismiss this as pedantic rambling. In effect, Ed Sapir and Ben Whorf said "that the structure of a language determines a native speaker's perception and categorization of experience".
In other words, as my erudite Anthropology professors used to explain: Language determines thought. And thought determines one's personal reality.'
People widely assume that an observer is truly independent and isolated from what is observed. But is this true? The answer is clearly 'no' in the very small world of quantum mechanics. I am agnostically skeptical about larger phenomena.
But you have to care about philosophy of science and epistemology (how we 'know' what we think we 'know') to care such core consciousness issues. Most people seem to view them as a boring bother. Or as simply a sideshow for small-minded dilettantes.