# Forememory: What could prevent reiteration from working?

I use forememory instead of foresight, due to how the ability works.

A cunning and creative person can remember five minutes into the future, and are smart enough to exploit it in any way possible. For simplicity, I will name the person "Abe". They are the only one with this ability, so others seeing the future and changing it won't be a problem. Recalling the previous five minutes and recalling what occurs in the next five minutes are exactly the same for this person. They could spend a few seconds remembering, then take action upon this. Why can't they abuse their power by reiteration (write a note, see his future self writing the note, repeat until two minutes foresight can be five years foresight)?

Clarifications:

Abe's five minutes forememory are of what will happen if he didn't remember the future. The act of remember automatically changes the future. However, since the forememory shows Abe what happens if he didn't use the ability, he can do reiteration: If Abe "remembers" nothing happens, Abe doesn't need to take action, but if he makes a warning to his past self, his past self will change their actions, because Abe changed what he did. One possible result is that as soon as Abe can use this power, Abe gets warnings of the future regardless of what he does. This is one reason why I want to "disable reiterations" (although, it would be an interesting story where a person can warn their past self, and the story is how every action they take they still regret their life and warn themselves).

What is reiteration? Skip this last paragraph if you already get it and don't want my clarification of what I envision the ability to be. If you say "pencil" and wait a minute, you will have little difficulty remembering what word you said. It will also take you only a few seconds to remember this. Then, you say the word you remember to a friend. The friend won't have memory of what you originally said (like Abe can't remember 10 minutes ahead), but can remember what you just said (like Abe remembering 5 minutes ahead). This can be "reiterated" until you have a chain of any number, as Abe can do to remember into the future of any distance. In the case of Abe, he can do a similar process. Let's say nothing interesting happens to him for a few hours, but he vigilantly uses his forememory just in case during the whole time. Then, an ambush happens and he is trapped. The ambushers plan for his ability, and wait 5 minutes after blocking all escape routes before revealing themselves. Abe remembers the future out of habit, and notices future Abe getting hit from behind, just like you might feel pain in a memory. Abe quickly writes "Ambush 18:41" on his palm with a marker always kept in his pocket or nearby. Now, the story changes: Abe has nothing happen for a whole week, but vigilantly uses forememory and notices his future Abe writing down "Ambush 18:41". This is because the forememory shows what will happen if he didn't use the ability. What would happen is that he writes the warning on his palm as soon as he knows. Since Abe can see the warning 5 minutes in the past, and the warning is made 5 minutes before the event, Abe has 10 minutes preparation. If Abe writes a warning of the warning "Ambush 18:41" on his palm, the previous him gets 15 minutes of time. Reiterated, Abe could go until the moment Abe woke up that day. If Abe is willing to sacrifice sleep and only sleep 4 minutes at a time, he can sleep 4 minutes (with a loud alarm), then use a minute to check the future and write down a warning on his palm if necessary. If Abe ever fails to keep this chain working (like waking up late), Abe will notice this with the futurememory, and take action to correct it. Note: 18:41 is military time 6:41pm. If Abe desired, he could also write the date instead, or use an extra five seconds for more information if needed.

• Ever played chinese whispers? Mar 19 '19 at 22:49
• In the movie he not only sees, but he also hears. So it would be easier for him to simply say out loud what he will see two minutes later. Mar 22 '19 at 12:34
• And about dodges, they are just showing how the power works. Every posible movement he can made to evade or get shooted, so he is just moving in "the best" path. Mar 22 '19 at 12:35

## Future you has faulty future memory

So, when you look into the future, you are not seeing the actual future. You are seeing a possible future (since seeing the actual future would cause all sorts of paradoxes). The world in this possible future has some differences. One of them is that your future memory is faulty in this non-existent world. In particular, if the you in your future vision tries to use their own future vision past what your own future vision could look, they will get a false reading. It will be plausible, but false.

This means that if you try to pass a note back by more than two minutes, the note will get horribly corrupted, even if its just 5 minutes and 1 second.

Alternatively, you could say that the you in the future memory has future memory as accurate as your own, but "recursing" causes cumulative errors. You can explain this in analogy to mirrors:

Notice how as you get deeper, the mirrors get darker. Likewise, trying to pass a note back 5 years would make it completely garbled. Even if the note is not garbled, the information it contains will reflect a horribly inaccurate future. You could try to recurse, say 15 minutes or more and probably be fine, but it wouldn't be as accurate as five minutes.

• That makes sense. Anyway, reading the future notes every few minutes will change each successive iteration of the future, blurring it more and more the farther you go forward. Apr 10 '19 at 21:43
• Exactly, our own regular memory isn't perfect, so why should Abe's fore-memory be? Nov 21 '20 at 2:17

If you do this, you are committing to writing and reading a note every two minutes for the next five years.

Even if it's not the same you, because you branched from that timeline by seeing or acting on this information, for this to succeed, there must be some potential chain of custody where you stayed awake for five years straight writing and reading notes to get this information back to yourself.

I shudder to think of the kind of future that you're trying to avoid that would make that level of effort worthwhile, and marvel at the dedication and willpower that would be required to successfully push the note that far back.

• I don’t think that’s true. Suppose I see “me+2” writing a note at 11:02, and write it down at 11:00. That means I got information from 4 minutes into the future, and don’t have to do anything at 11:02. But you can apply the same logic to me+4 from the original timeline, and so on. There must be timelines where I wrote the note at 11:02, 11:04, 11:06 etc., but in any single timeline, I only need to write the note once. If it is possible for me to be woken up by urgent premonitions, then even sleep is not an issue (I will be woken only once in a given timeline). Mar 20 '19 at 2:15
• @bobtato - I dunno, I think it would not be so easy. Even if you do only write one note in any one timeline, I think you would actually have to, ah, "intend" or "commit to" the five-years-note-writing-marathon. And I mean really, really commit to it, intend it, be willing to do so. You handwavily say "I'll do this and that and the other in just two minutes" and then you get distracted and not do it, and there goes your chain-of-notes. And you'd have to be willing to commit without benefit because each you writes their note in a timeline where they didn't even get the five-year-note! Mar 21 '19 at 8:26
• It's worth noting that prolonged lack of sleep is fatal, passing through periods of hallucination and psychosis inbetween. I'm not certain it's possible for one person to do this, which is good for the question I suppose! Mar 22 '19 at 12:12

The future changes only if the person attempts to recall their "future-memory", regardless of whether an action is taken based on the new information (for example, unconscious hesitation messing up the events slightly).

The act of foresight itself changes the future - and continually looking forward instead of taking action continually invalidates the previously anticipated future. There may be a hard natural limit to how much of the future can be foreseen - somewhat like thermodynamics limiting absolute possible efficiency of a process (at well under perfect efficiency). Like PyRulez suggests, everything beyond some limit becomes indecipherably fuzzy.

Or, alternatively, your seer might actually be seeing all possibilities - and the limit might be the power of the mind of that person. For ten seconds, you might be able to comprehend all the possible futures. To look forward two minutes, you're really just estimating. For ten minutes, no mind could hold that many possibilities. And to look forward at every possible future in the next hour would require more mental processing power than is possessed by the entire human family.

• Basically every iteration is a new set of branching paths with many possible outcomes based on your decisions. these build on top of each other exponentially with each iteration. The brain can only process so many contingencies, likely 7 iterations is the max, based on how many discrete pieces of information the brain can handle. but you also have the problem of reading and accessing memory, it will quickly take longer to read/recall the stack of notes than the cooldown times.
– John
Mar 20 '19 at 3:55
• This especially works with the Quantum Mechanics theory of uncertainty. Since particles don't establish a defined path until being observed, seeing what they are ahead of time determines their path early, changing the outcome. Plus there's the concept of true random creation and destruction of antimatter and matter particles Mar 22 '19 at 17:45

Context.

The actual information content of your future sight is pretty minimal. Instead of seeing everything that's going to happen, like a time-traveling video stream, you get glimpses of important facts. Your brain then slots those facts into the context it already has, making a coherent narrative out of them. You "remember" a sharp pain in the leg, you see a man with a gun, your brain assumes that means he's going to shoot you in the leg and you dodge. Because the timescale is so short, usually the context hasn't changed very drastically and the impulses and impressions you get from the future make intuitive sense.

(Incidentally, the name "future memory" for this sort of foresight is very accurate, because it's analogous to how normal memory works. We don't remember things as hard data: we remember impressions and associations, and when we need to recall directly, our brain reassembles the context on the fly. This leads to a number of well-known tricks and faults in recollection, like conflation of different events or even outright invention of things that never happened.)

However, this means that your ability to capture discrete, written information from the future is pretty limited. You might be able to grab a few snippets, like what number someone's about to pull from the lottery bin, but a whole composed message would be beyond you. You would spot a few details and have to fill in the gaps - but because it's present-you that's filling in the details, not future-you, you don't necessarily know how to interpret what you're remembering. The more you do this in a row, the more pronounced these errors become, until you're mostly working off of your present knowledge and ability to make guesses about your future state. That's a handy skill, but it's intuition, not precognition.

• If it is future memory, then it is only about what you will know in future, that itself limit what information can you try to send back (just what you discovered personally).
• Also as you can see just two minutes ahead, you have only two minutes to read and write the full message (and errors are propagating with it - once you make mistake in number that digit is lost/mangled forever)
• You cannot sleep all the time, or the line is broken and lost
• More over I would put a small penalty on using that ability - not big, but cumulative (makes you more tired, like pushing heavy weight or solving hard logical example) - so it is not a problem use it occasionally for two or three minutes, but for ten minutes it accumulate to serious tire and for an hour it can knock you down temporary.
• Using it two minutes, rest five minutes and you are ok as if you just sit idly all the seven minutes (still you want to go sleep after like 16 hours) - after all it is extraordinary mental task to use future memory and interpret it right.
• So there is a physical limit to number of iteration, until you are forced to stop (and as author you can set that limit as high or low as you see fit, maybe little longer for extra important messages - more effort done)
• As was mentioned, it is "just" memory, so anything more complicated get interpreted and be retold each time (Chinese whispers), so each iteration is more garbled anyway. In my experience five steps nearly assure even simple sentence to go wrong (that is 10 minutes max).

The “cool-down period” seems like a sufficient solution. If I can’t use the ability for x minutes after the last time I used it, then when I observe myself 2 minutes in the future, that version of me cannot also be looking at the future, since he/I used the ability 2 minutes in his past.

For this to make sense, the ability would need to be a one-shot thing; when you “fire” it, you remember everything that will happen in the next two minutes, but you have to wait at least two minutes before “firing” again.

If for some reason you don’t want to use that restriction, there is still the “butterfly effect” argument: the further back in time you send a piece of information, the greater the chance that you change history so it never ends up being true after all. However, this doesn’t apply equally to everything – if you see the Earth being hit by an asteroid in 3 years, it is highly unlikely that your reaction will inadvertently change that outcome.

Also, as noted in other answers, each iteration introduces potential errors – if you write something down from memory 5,000 times, it’s unlikely you will get it exactly right each time (though again, “asteroid strike June 7 2022” is hard to get wrong).

And sleeping for more than two minutes will break the chain, which rules out recursively seeing more than a few days into the future (unless the memory is shocking enough to wake you).

A completely different, but arguably more self-contained approach would be this:

1. The ability works continuously – your memory simply starts 20 seconds ahead of the present
2. Recursion is possible – you premember premembering stuff that happens 20 seconds after 20 seconds from now, and so on. But you just can’t process more than 5 or 6 levels of recursion, so in effect, you can’t resolve more than 2 minutes into the future. This would vary depending on the complexity and intensity of the future stimulus; you might foresee being electrocuted 5 minutes in the future, because it would grab your future attention so strongly.
3. Writing stuff down (or equivalent) is not a workaround, because if you write something down now, you won’t decide to write it down 20 seconds from now, so you won’t premember doing that in the first place. In other words, it creates a paradox to physically react to something beyond the current horizon of your memory.

Consider things from the perspective of the you who writes the note instead of the one who reads it.

If something bad just happened, and you can write a note telling your past self to do something different, then you rewrite the last couple minutes of your life with a (hopefully) better version. That doesn't seem like a bad deal; it's basically the same as trying something again, and then forgetting the first time you tried. You forget more than that every day.

But if you want to send a note back five years, you will necessarily be erasing the last five years of your life. Are you precisely the same person now that you were five years ago? If not, are you willing to effectively end your life so things will go better for past-you?

Even if your personality hasn't changed much in that time, any message going that far back is likely to change a lot. Do you tell yourself to get a different job? Even if it's in the same city, your schedule will change enough that you'll interact with different people, on and off the job. Hopefully you don't especially like any friends you've met since then. In turn, most of the conversations you had in the last five years never happen. Is there anything you learned, either in the conversations themselves, or by reading up on something that was mentioned? That knowledge is now gone. Have you created anything in that time? It may never be made. For that matter, have you had children in that time? You may have children in the new timeline, but absolutely not the same ones. And all of these consequences potentially apply (to a lesser extent in most cases) to anyone you interacted with over the last five years.

Even if long-term use of this ability is easy to accomplish, it is not a decision that will be made on any sort of regular basis, and it is a severe sacrifice even if it's deemed worth it.

Of course, there's a period of time between the two extremes. Some quick googling suggests that you can buy lottery tickets as little as 15 minutes before the winning numbers are drawn. All I've done in the last 15 minutes is write this answer, and I'd be willing to lose that for a few hundred million. So if you're reading this, it means I was unable to send that message.

The very act of looking at the future changes the future which prevent iteration

You can look at the future, as it is at the time of you looking, but by looking, you choose the best path which means the future you just looked at is no longer the future you saw. If the future has changed because you looked, trying to iterate to see more fails.

A way to solve for this is to make the memory/visions of the future come in not 100% clarity. Think of how in the movie Pitch Black how Riddick sees the world. It is semi garbled. (does not have to be uni color, but does help in the obfuscation) . But by having the information not 100% clear there is active thought needed to clarify and understand. Text is difficult to read if not of billboard size.

This simple implementation would be enough to not allow exploitation into 5 years of the future while still keeping the ability highly useful. (again refuring back to that Sci Fi movie where a little foresight lets him fight effectively the final necromonger boss.)

Short sweet simple solution is the best!

Time blurs. There's not a hard cut-off after two minutes, that's just an approximation. Instead, quantum uncertainty effects stack up to make future 'memory' more and more uncertain as you look farther forward in time - meaning that anything farther ahead than (approximately) two minutes is very unclear and unreliable. Writing a note doesn't help this, because two minutes in the future there are multiple possible versions of you writing slightly differing notes, and the further ahead you try to look the worse it gets. Try to look ten minutes ahead, and there are billions of possibilities and no way to distinguish between them - useless.

Because future you wouldn't care about past you.

Imagine something terrible happened to you (#1) a minute ago. You (#1) write out a note to warn an earlier version of you (#2). You (#2) write a note for the next one (#3) and make whatever change you (#2) hope works to prevent terrible thing from happening. You (#1) still live with it having happened. You (#2) might fix it, but also get no benefit from writing the note for the next guy (#3). The only benefit is for someone else.

So, why would any of you write the note, especially when you are still grieving (#1), or preparing to prevent tragedy (#2+)?

Also, were you looking at the future, two minutes ago? Otherwise no one would be there to read the note.

It's funny you mention Next, because it's loosely based off a Philip K Dick short story, The Golden Man. That guy spends most of his life, just sitting around, ignoring the present, while he looks at the future. He's not exactly well adjusted.

Every time you look into the future, you instantly change something about that future. If you focus on trying to remember something, you spend time in doing so. If you sped three seconds remembering a specific event, that results in you not spending three seconds doing the thing that led up to that specific event. It's really impossible to remember anything vividly without focusing on it, which means you cannot multitask and have the same degree of memory or detail of memory. You HAVE to stop for some period of time to think about the future, which over iterations will build up to minutes and hours, which will in turn massively change your current future with the butterfly effect. Think about it in context- your person will never know when he will have a chance to remember his message from the future. He has to spend ALL of his time trying to remember the future, which would be an enormous waste of time and potential. If he misses the message from five minutes in the future, that means he has lost the original message for good. Imagine it like this: #1 is the person sending the original message, far in the future. Now, you are person #1200, and 5 minutes in the future you are person #1199. If you look into the future as #1200, you will have changed the future, possibly even causing #1999 to miss the chance to look into the future, breaking the chain. However, if #1200 does NOT look into the future, the future will not change, and the everything will be exactly the same as person #1 since it will be impossible to receive the message of any person in between. This means you have to be available in those five minutes when you can receive the message, which kind of reiterates what you said in creating the chain in the first place.

Now, this answer is different from others in the subtle difference between chance and actuality. True, in the timeline the message is intended for you only have to look into the future once in order to receive the message. However, as the person of that timeline has never received the message before, he has no tangible or immediate reason to look into the future, almost certainly missing his chance. In this scenario, the person would be lucky to have a long-term message manifest once in his life. Another possible scenario could be the pre-determination of a system, such as yours, in which a person is available and has the intention to receive a message at any time. This would require waiting for YEARS, doing nothing else but waiting for a glimpse at the future. This sort of inactivity would most certainly screw up his future, changing everything and making the information irrelevant. Finally, even if you set up a system in which the intended recipient of the message sends it back even further in order to make up for the time each timeline has spent waiting, there is still one glaring issue with the concept of time-traveling messages: You can't do anything about them. I mean, the moment you do a single thing different from person #1, you have lost that future forever. Unless future you is omniscient, there is absolutely no way you could figure out exactly what to do so that you could arrive in exactly the same future with only one thing being different.

There is honestly no way I could explore all of the possibilities of your future memory without brutally strict definitions about time and perception, which is something humans will probably never understand. I'm not even going to get into the different types of timelines and theories of existence people have created, from alternate universes to one continuous universe in which characters must disappear from one time in order to appear in another. My response covers only one of these theories of time, in which time travel instantly creates an alternate timeline and universe.

If you want a more brief explanation of each type of timeline, I would recommend you watch the short video down below. It gives good examples of each form of time travel as well as the implications of each.