> what if all the "points in time" just exist... They don't flow at all. This sounds similar to the "block universe", where the universe is a 4D "block" with a

> what if all the "points in time" just exist... They don't flow at all. This sounds similar to the "block universe", where the universe is a 4D "block" with a certain height, width, depth and duration; where change over time (e.g. an object fading from black to white) is just like change over space (e.g. an object with a colour gradient) > since I can only remember "backward" through time, at every point it appears as if I have progressed through time. I've seen a related idea come up in discussions of "Boltzmann brains" (can't find a reference ATM): if the 'arrow of time' is due to increasing entropy, then regions where entropy is decreasing (e.g. an open system radiating heat) could be thought of as experiencing time backwards. What we see from the outside as, say, a collection of photons entering a camera lens and bleaching an existing image off the film; from the inside would be experienced backwards as the taking of a photograph. > Even if I have perfect knowledge of the present, there are some things I can not predict about the future That might also be true about the past! There's an unsolved problem in physics called the "black hole information paradox", which points out that if we have a bunch of mass (like a star, or a vast number of elephants floating in space) we might calculate that in the future they'll collapse down into a black hole. Yet if we have a black hole, there's no way to know what it was formed from in the past (stars, elephants, etc.). Black hole formation appears to lose information (like an AND gate), but that's strange since all known microscopic laws of physics (i.e. not the second law of thermodynamics) are reversible.