There’s a difference between understanding the world objectively (or at least trying to, anyway) and experiencing it through an exclusively objective framework. This is essentially the problem of qualia — the notion that our surroundings can only be observed through the filter of our senses and the cogitations of our minds. Everything you know, everything you’ve touched, seen, and smelled, has been filtered through any number of physiological and cognitive processes. Subsequently, your subjective experience of the world is unique. In the classic example, the subjective appreciation of the color red may vary from person to person.
The only way you could possibly know is if you were to somehow observe the universe from the “conscious lens” of another person in a sort of Being John Malkovich kind of way — not anything we’re likely going to be able to accomplish at any stage of our scientific or technological development. Another way of saying all this is that the universe can only be observed through a brain (or potentially a machine mind), and by virtue of that, can only be interpreted subjectively. But given that the universe appears to be coherent and (somewhat) knowable, should we continue to assume that its true objective quality can never be observed or known? It’s worth noting that much of Buddhist philosophy is predicated on this fundamental limitation (what they call emptiness), and a complete antithesis to Plato’s idealism.
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