I can agree that saying something such as that matter isn't real IS something far more seemingly profound when one is high. Beyond that, I consider debating such a notion utterly pointless.

Time is a useful concept that enables us to organize many things in our personal life and societies in general. I think that it was Alan Watts who said that time is a man made concept and doesn't exist in terms of galaxies.

The past whether it be yesterday or last week or last year only exists as a memory and the future is mental projection. Nobody has ever visited the past or tomorrow except in the realm of memory recall or imagination.

Interestingly, Neils Bohr was a awarded a Coat of Arms by the Royal Danish Court for his contribution to physics. He designed his own heraldic shield. The Latin inscription at the top of his heraldic shield reads Contraria Sunt Complementa (opposites are complementary) easily lends itself to trivial interpretation by New Age Gurus. Of course, you could spin that one out forever. I wonder did Neils Bohr understand or grasp something that eluded Einstein..

As with everything else in this life language plays a major part, in particular, how we use language to describe the world or our experience or label a person or act and as such, requires scrutiny. Belief may considered a source of comfort for the believer and requires little or no effort of thought, however, belief is not merely confined to religious viewpoints.

"The whole problem with the world is that only fools and fanatics are always so certain of themselves, and wiser people so full of doubts." Bertrand Russell

I believe we all live in an eternal NOW with no past and no definite future. As for when we come on the scene by being born, it varies. Some of us leave before others do. That's it. As to what our substance is people continue to make it all up. What is quantum and what is a multi-verse? Nice ideas for sci-fi and TV shows. Well, it might exist, they say.

Let's test my idea by going back in time by only a week. The others that your mind takes with you on this time journey show up but they also have to be present in the NOW as well. Oh, quantum will fix that, but do they have the same memory of a week ago that you have? Probably not. This time traveling event has to come from all minds involved collectively OR it comes from only one person's memory. That comes across sort of like a history book. Nothing is actually real here and we just skim the surface. If we all travel backwards into "Leave it to Beaver" who's version of the program would we be in? What concept of the 1950's is real here. Sort of like beauty. It is all in the mind of the beholder.