The perception of a present "now" time flowing from the past to the future is an illusion. It is an illusion because it give you the impression that the universe is just a bubble of reality travelling form its source at the big bang to where ever it is going in its future. Presentism is the view that only present objects exist. Thus, you and the Taj Mahal would be on the list, but neither Socrates nor any future Bases on Mars would be included And it's not just Socrates and future base on Mars, either -- the same goes for any other putative object that lacks the property of being contemporaneous to us. All such objects are unreal, according to Presentism. One alternative to Presentism is Eternalism, which says that objects from both the past and the future exist just as much as presently observed objects. According to Eternalism, non-present objects like Socrates and future bases on Mars exist in block time, even though they are not currently present to our perceptions. We may not be able to see them at our perceived moment, on this view, and they may not be in the same space-time vicinity that we find ourselves on our own subjective "now time", but they should nevertheless be on the list of all existing things. I like to use a "surfing carnival" analogy and if one is a presentist they believe that their lives are analogous riding on a board called "present" within a single wave called "reality", and when they a wiped out that is the end of their lives that is it and the wave just keeps rolling on without you. There would a strong ontological bias between the reality where you are dead and the reality where you are yet to be born as you only continue in the wave of reality where you are dead. An eternalist like me believes that all the events during the carnival are equally real, and not merely a single surfer surfing on a single wave so when you are wiped out then all the other waves and surfers are equally real. In this case there is no ontological bias between the events before you are born and the events after you die. So you can say you are both equally yet to be born and dead in a the realm of the block universe, with no more bias to being dead that not being born.