[Serious] Is the Past Real?

[Nay_Sayer]

According to my student loan, It certainly did, and with interest.

[polymath257]

If you should ever find yourself standing a few kilometers from ground zero of a thermonuclear hydrogen bomb, please note that you will be experiencing a past event that only lasted a millionth of a second.

You don't experience past events, you experience present events.  In the case of the bomb, you experience a flash of radiation and a blast of air.  These present events have a cause in the past, however.

I would disagree with that. The brain takes time to process the information from the senses. In fact, it can take fairly substantial fractions of a second to do so. So, the actual experience is always delayed from even the sensory event, let alone the event being sensed.

In the case of, say, a nuclear event at the site of an individual, it would be likely that no experience would be had at all since the vaporization of the body would happen much faster than the nerve signals and the brain processing. A nuke a kilometer away  would be a different matter, depending on the size and speed of the fireball.

[Anomalocaris]

I think the analogy may be if we are disembodied brains rigged to receive made up, but fully coherent, sensory inputs synthesized by a computer, according to an algorithm and not analogous to any actual present event or present effects of past events, how would we know?

Take it one step further, let’s say the computer actually has the capability to reach in and overwrite our memory in a coherent way,  how would we even know not only whether the past as we perceive it now is real, but the past as we remember is how we actually perceived it?

[The Grand Nudger]

Interestingly enough, it almost certainly isn't. We don't store memories. We create them on the spot as needed, and they apparently have more to do with utility in present than accuracy of detail in past.

[Anomalocaris]

Interestingly enough, it almost certainly isn't.  We don't store memories.  We create them on the spot as needed, and they apparently have more to do with utility in present than accuracy of detail in past.

We certainly store memories, at least the cliff notes versions.   Otherwise what we make up on the spot as faux memories would have to be essentially random.

[The Grand Nudger]

The cliff notes versions appear to bve simple things like dates and overwhelming things like emotions - though we're equally adept at forgetting one or both all the same. The things we make up on the spot to create a narrative beyond the memorization of a date, or simply remembering feeling jilted (without remembering the experience) aren't random, they're a product in large part of a present moment. They're manipulable, too. Just as we can alter present experiences with chemicals, for example..so too can we alter present experiences of the memory of past moments.

[Neo-Scholastic]

It seems like pretty much every eternalist or block theory proponent implicitly references a principle of sufficient reason, i.e. evidence in the present has a reason (past occurances) for its current existence.

[LinuxGal]

It seems like pretty much every eternalist or block theory proponent implicitly references a principle of sufficient reason, i.e. evidence in the present has a reason (past occurances) for its current existence.

In a block theory there does not exist a fact of where the present is located, or in which direction within the block the past light-cones lie.  A growing block theory can support these concepts.

[emjay]

OK I'll try and have a stab at answering the original question.philosophically. .. do I think the past and future are real?... no, I don't think I do. From the point of view of determinism any time t just seems to basically represent a theoretical global state of the universe, so in that ongoing process of physical change (of that global state), only the current state is real, a past state was real, and a future state will be real and like all the other states, is inevitable.

I know there may problems with this view, from a modern physics and quantum physics point of view (about which I'm way out of my depth)... that hard determinism may not a tenable worldview any more, but it is nonetheless how I conceive of the universe at present, and frankly how I am most comfortable conceiving of it (hence my avatar... which still speaks to me as much now as it did when I first applied it)... even Einstein had difficulty letting it go I think, so I'm not the only one

But anyway, regardless of whether I think the past and future are physically real, I still think that, like I said before, we have some sort of psychological/emotional obligation to it, if not a rational/philosophically grounded one... ie for instance to honour the dead. But separating the psychological aspect of this from the logical, I suspect will prove to be... fuzzy.

[The Grand Nudger]

Is, was, and will be all modify tense. The language implicitly assumes that each is real, as the modifiers are synonyms for the object in question.