As I heard from Rabbi Simon Jacobson at one of the conferences of Chabad Rabbis – it’s a very deep subject but the essence of it is, that we cannot say that reality is real – in fact the word for Olam / world in Hebrew comes from the word Helem / concealment – what reality is, is a concealment of real reality – and the bottom line is as follows – that we receive Revelation – but the thing about Revelation is, that if our reality is not real, it is a concealment of what is real – then what we know is only like a single flash of lightning, and there is infinite to come