1 Iki Piki: {walking out of the hospital} We still owe Paris, Serron, and Quercus for the first operation. Now another 90,000 credit hospital bill, plus we owe the loan shark 20,000!
2 Serron: Yes, but we have a spare set of internal organs now!
3 Iki Piki: Fat lot of good that'll do us when the loan shark breaks our legs or puts us in cement shoes. We need to raise cash, quickly.
4 Serron: Well we have spare organs now, right? We could sell a set on the black market!

I thought Iki Piki should provide a brief summary of the financial situation as it stands at the moment, since a lot of posters on the forums have been expressing confusion as to why they needed to raise another 90,000 credits if the first hospital bill had already been (somehow) paid.

And if you think that's complicated, here's some of what people have been saying about what's going on with the organs (edited slightly for clarity):

Iki Piki got his "splanch" from his future self, right? So, let's assume he takes a week to get into the time machine. So his future self is one week older, and so is his organ. Well, this organ goes to present Iki Piki... so now he has an organ that is one week older then himself. One week later, he travels in time and becomes future Iki Piki, who is one week older, but has a two week older splanch... not to mention that his organ has now undergone two removal and replacement surgeries... and this could go on and on forever, and at each iteration, the splanch gets one week older, and goes through 2 surgical procedures.

Followed by this:

I had the same theory before:

My theory on this was that this is a semi-closed loop. They take the organs from their future selves, travel back in time and lose them, where a new set of "past them" take the organs. The loop is semi-closed because in this way the organs continue to age, and will at one point die, thus ending the loop.

Which was preceded in the same comment thread by this from another person:

Okay, so, the simplest form of the time loop goes something like this...

• Iki Piki 1 (IP1) and and Serron 1 (S1) and their respective organs (O1) are born/hatched/budded/whatever.
• IP1, S1, and O1 get taken prisoner.

Time T:

• IP2, S2, and O2 arrive in the past and are put in the cell with IP1, S1, and O1.
• IP1 and S1 have O1 removed.
• IP2 and S2 have O2 removed.
• IP1 and S1 steal O2 and have them implanted.
• Disposition of IP2, S2, and O1 is unknown at this time.
• (Current strip present)
• IP1 and S1 somehow travel back in time to Time T, becoming IP2 and S2, and carrying O2 with them.

So... if this is the correct form, where did the organs (O2) that Iki Piki and Serron are currently using come from?

An interesting question indeed. Followed by another reader with:

I have to write this down to get it straight. I was right about the O1 being still around to be stolen, but I thought it was IP2 & S2 that stole them, not IP1 & S1.

So how does this work up to the repeat ...

• IP1 & S1 deal with a black marketeer and end up in a cage
• IP2 & S2 arrive from the future to free them, but end up in the cage
• IP1 & S1 wake up in a dumpster with their organs (O1) missing
• IP2 & S2 are also dumped in an alley for dead, with O2 missing
• S1 steals O2 and they have them transplanted into their own bodies
• IP1 & S1 find O1 and have them implanted as a back up to O2
• IP2 & S2 recover from being dumped, because they have O1
• IP1 & S1 go back to rescue their past selves, becoming IP2 & S2

So at the time of first implantation, the organs are the age of IP1&S1, plus the time it takes them to find a time machine. So is it an infinite loop?

I'm running along the road. My hat blows away, but in a moment I catch up to you, and your hat has just blown off, so I grab it. I run along a bit more and find my original hat, so I pick it up and put it on, then put your hat back on top of mine. Now you don't have a hat, but I let you catch up to me and grab mine. However, I was wearing two hats, then doubled back so you could have a hat. Therefore you don't need to double back to give me a hat, because I've already got one, so the loop is not infinite.

Does that work?

Responded to by this:

Actually, they had O3.

Try it like this (following just the current IP1 and S1):

• IP1 and S1 have their O1 removed
• IP1 and S1 replace them with O2 (removed from IP2 and S2).
• IP1 and S1 find O1.
• IP1 and S1 have O1 inserted along with O2.
• IP1 and S1 go to the past, taking with them O1 and O2.
• IP1 and S1 have O2 removed, but are left with O1.
• Meanwhile,their past selves (IP3 and S3) have O3 removed.
• IP3 and S3 steal O2.
• IP3 and S3 find their O3 later.
• IP1 and S1 (the ones the comic follows), have O1, which they started with.
• IP3 and S3 have O3, which they started with, but they also have O2, which are stuck in a loop.

This way, the loop is infinite (unlike your hat analogy), because it features three sets of organs (current, future and past), of which two are in their original timelines, while one (O2), travels infinitely through time. Well, not infinitely, but until they grow old enough to fail, thus dying inside IPn and Sn.

Temporal mechanics can be such a mess.

However, if they decide to have their original organs removed when they go back to the past, and have the ones they stole from their future selves as spares to use later, there wont be a loop, and the organs would age just one day (or so) more than their owners.

At which point one of the readers decided the only way to solve this once and for all was to draw diagrams:

So far, here's what we know happens. Right now we're at the point where they've stolen the case of organs (diagram A). We know that they'll go back in time at some point, and since there are two sets of organs around we're assuming that they get their organs stolen after doing that.

It seems pretty clear that they get the organs of the future versions of themselves (diagram B). Assuming that Serron wasn't mistaken in which organs he grabbed... but he seems the trustworthy sort, right? Maybe he was mistaken and they took their original organs (diagram C).

Which as someone else pointed out is actually not so far fetched:

... because according to 1831, they will have two sets of organs in their bodies when they go back to the past.

Which just led to further confusion:

I've just sat down with a pen and piece of paper to sort this out, and as far as I can tell, it's not an infinite loop at all. For starters, there aren't 3 sets of organs. Technically, there aren't really even two sets of organs, but I understand that for many people it's more convenient to talk about them as though there are two sets.

• IP & S have organs removed.
• Due to the time travel they later indulge in, IP & S get a future version of those organs reimplanted (same organs, though).
• IP & S find the original versions of their organs.
• IP & S will get those original organs implanted as well, so their present selves contain "two sets" of organs, although one set is really just a future version of the same organs.
• IP & S then travel back in time and have one of those "two sets" removed - in this case, the future version, leaving them with the original version (since it's stated that the originals will be hidden as 'backups' and presumably after the future set is removed they'll be repositioned to their proper places).
• IP & S then presumably time travel back to their new present, with their organs in their bodies, and will continue with those organs being exactly the same age as the rest of their bodies, since the organs have travelled along exactly the same path as IP & S took during the whole event.

That's looking at it from Iki Piki's and Serron's points of view. Something I have done yet with my pen and paper was to look at it from the organs' pov. Now seems like a good time. :)

• They get extracted and put in a case.
• They're found and implanted as 'hidden backups' in IP & S, who already have functioning organs in place. (Hmm, from where, exactly?)
• They time travel back and aren't removed from the time-travelling IP & S because it's the other set that they have removed.
• They time travel back to their new present with IP & S and continue on happily.

You know, going through it this way - it's not that the organs wind up in an infinite loop. It's that there should never be a second set for IP & S to wind up with two sets in their bodies. Where did those "future organs" come from? At no point in the loop from the organs' point of view are there ever two sets of organs.

Meep.

And it gets better:

Yeah, that "Meep"? That's what Iki Piki's complaining about, and what I was talking about in my earlier post. If Serron's plan is executed as presented*, there are two sets of organs, one of which didn't come from anywhere.

There's the O1 set, which Iki Piki and Serron were born/budded/whatever with in their respective usual fashions, and which, after all this time travel mess is done with, they'll ultimately end up dying with in their respective usual fashions.

And then there's the O2 set (which is the set that they're currently using), which have no origin or ultimate destination, are neither created nor destroyed, but exist in an endless loop of arriving in the past from the future, persisting through the present, and then in the future travelling to the past again. And at some point in there being temporarily implanted into a couple of idiots.

This is easy enough to fix... they just have to leave the ones they just found for their past selves to implant and keep the ones that they're currently using instead. That turns the infinite loop into a single-pass loop, where there's only one set of organs that's merely doubled back on itself for a while.

* This may not actually be possible.

Then the following riposte:

Ah, but here you didn't count what happens to the future set of organs, that get removed from them, the ones that their future selves used as backup, and that their past selves will use as backup, the ones that indeed are in the loop. The ones that started nowhere, but end up dying in their hosts.

Followed by this mind-bender:

So you're all okay with there being two complete Iki Pikis and Serrons, standing there in that jail cell, but not that they both come equipped with organs? There are three splanches in the cell just before IP1 is called to surgery: One in IP1 and two in IP2. IP2 takes only one splanch back to the future so the second one is left behind for IP1, so that he will have two when it is his turn to be IP2.

Here's my splanch-eye view of the proceedings:

• Splanch is born/budded in IP1 and hums along happily until one day it is removed and placed in a case.
• Case is picked up, taken to hospital, splanch finds itself implanted behind a IP1's stomach, but there is another splanch already in the body, in the normal location.
• Two splanches coexist inside the host body and then travel back in time.
• The other splanch is removed and the splanch we are following is alone again, and presumably its host gets back in the time machine and returns to the future.

CURIOUS! Telling the story of S and IP there is a clear point at which they become the "future" versions of themselves, but because one splanch is behind the stomach and the other isn't, our splanch observer doesn't get to suddenly be the future one.

But if the original splanch, the one implanted second, is put in the normal location and the future splanch is the one hidden as a back up, then how does it work:

• Splanch is born/budded in IP1 and hums along happily until one day it is removed and placed in a case
• Case is picked up, taken to hospital, splanch finds itself implanted back where it started in IP1, but a mysterious second splanch is already hidden behind the stomach.
• Two splanches coexist inside the host body and then travel back in time
• Our splanch is removed from IP2 and placed in a case.
• Case is taken to the hospital, where our splanch is implanted just in time to keep splanchless IP1 from dying.
• Our splanch undergoes a second operation to move it behind the stomach, as it sees its past self implanted in the normal location.
• Our splanch lives on to the future until its host finds a time machine and travels back in time.
• This time our splanch is the hidden one, so it stays in the host and watches the past version of itself be removed.
• Our splanch, in its host, escapes and presumably returns to the future.

That is very cool: that a paradox should get worse depending on where a splanch is implanted in the same body. That the splanch sees going back in time twice while the host only goes back once. But that makes sense because there are for a while three splanches (two in IP2, and one in IP1, when they are all together in the cell) and thus two time journeys are necessary. But there aren't two uses of the time machine, it's just that the splanch experiences the same time journey twice.

And now, briefly de-indenting one level, we return to "I had the same theory before:":

My new one sounds even weirder:

They are actually going to steal the organs and place them in a convenient place for their past selves to find. Then, when they wake up, they nick the second set of organs, and leave the third for their past selves to find, take to the past, and continue the loop.

This last comment was written before it was revealed that the "convenient place" where Iki Piki and Serron leave the extra organs is inside their own bodies. The final conclusion:

No, the organs don't get infinitely older - it's the same set of organs, really. There's only ever one set of organs, and one Iki Piki and Serron. They just get shuffled around a bit.

"Shuffled around a bit." I like that description. Hopefully some of you are feeling a bit shuffled around after digesting all of that. :-)

---

2018-10-27 Rerun commentary: After this comic and the above annotation were originally published, there was a further flurry of discussion on the forums, which I won't go through in detail here (you can read it there for yourself if you wish).

But then at some later point a reader (forum denizen AlienAtSystem) decided to try his hand at drawing some more diagrams to hopefully illustrate things in a simpler manner. I now present them here.

These diagrams show a schematic presentation of Iki Piki's body and his internal organs at various times throughout the story arc. (A similar diagram could also be drawn for Serron.) In the diagrams, the cyan ellipse is Iki Piki's body. The smaller coloured circles are splanches. The left side of the ellipse representing Iki Piki's body is the normal location for a splanch. The right side is "tucked behind the stomach". Time progresses down the page, and each horizontal row shows the state of affairs at the labelled time.

This first diagram shows scenario 1, explained in words after the image:

1. Iki Piki is born. He has the usual one splanch (red) inside him, in the usual location.
2. Iki Piki ends up in the organlegger's cell. There he meets his future self (shown on the right of the diagram). His future self has two splanches, one in the normal position (blue), one tucked behind the stomach (red).
3. The organlegger harvests a splanch from both the original Iki Piki and the future Iki Piki. The splanches removed are now shown outside the bodies. Future Iki Piki has two splanches, but because one is tucked behind the stomach (red), the organlegger doesn't notice it, and he only removes the one from the normal location (blue).
4. Original Iki Piki discovers the organ case containing the splanch removed from future Iki Piki (blue), and has it implanted in the hospital. Naturally, they implant it in the usual place, on the left side.
5. Original Iki Piki discovers the organ case containing his original splanch, removed three days ago, and has the original splanch implanted back into him as a spare "behind the stomach or something". In this scenario, this is literally what happens. The original splanch (red) is implanted behind the stomach, leaving the "future" splanch (blue) in the normal location.
6. Time travel occurs, sending original Iki Piki back in time, where he is now "future" Iki Piki. He meets his original past self in the cell, and has the splanch in the normal location (the blue one) removed by the organlegger. This leaves future Iki Piki with his original splanch, now tucked behind his stomach.

From the diagram, you can follow the red arrows to see the path of the original splanch. It's removed once from original Iki Piki, then re-implanted tucked behind the stomach, where it stays. This splanch is only removed once. But there's another splanch. The blue one follows a closed time loop. It first appears in future Iki Piki, in the normal splanch location in his body. The organlegger removes it, then original Iki Piki finds it and has it implanted in the normal location. Then when Iki Piki time travels, he takes this splanch with him to the past, where the organlegger finds it in the normal location and removes it, thus completing the time loop.

Now, whether this makes sense or not depends on your views on time travel. Some points to note:

• Iki Piki's original splanch (red) doesn't loop through time. It's removed once, re-implanted, and then Iki Piki simply keeps it forever after, despite the fact that Iki Piki may travel through time in toto. The splanch never travels through time without him, so it's exactly the same age as Iki Piki, at all times. No problem.
• The mysterious extra splanch (blue), however, appears in the cell, is removed from future Iki Piki, then is implanted into original Iki Piki three days later. The later still, original Iki Piki travels back in time, taking the blue splanch with him. The total length of the time loop could be a few weeks or so. At every iteration, the blue splanch gets a few weeks older. It's doing this loop through time and aging throughout the whole process, each time. So... how old is this splanch? Will its cells eventually die of senescence? Where did this splanch come from, and what is its ultimate fate??
• Is this time loop a paradox, making this scenario impossible? Or is it stable and hence possible?

But don't despair, there's another possibility. I present scenario 2:

1. Iki Piki is born. He has the usual one splanch (red) inside him, in the usual location.
2. Iki Piki ends up in the organlegger's cell. There he meets his future self (shown on the right of the diagram). His future self has two splanches, one in the normal position (red), one tucked behind the stomach (also red).
3. The organlegger harvests a splanch from both the original Iki Piki and the future Iki Piki. The splanches removed are now shown outside the bodies. Future Iki Piki has two splanches, but because one is tucked behind the stomach (red), the organlegger doesn't notice it, and he only removes the one from the normal location (also red).
4. Original Iki Piki discovers the organ case containing the splanch removed from future Iki Piki (red), and has it implanted in the hospital. Naturally, they implant it in the usual place, on the left side.
5. Original Iki Piki discovers the organ case containing his original splanch, removed three days ago, and has the original splanch implanted back into him as a spare "behind the stomach or something". In this scenario, someone decides that the original splanch should go back in the original position, for some reason. (It could be at Iki Piki's request, or perhaps the surgeons just decide to do it this way.) So the original splanch (red) is implanted in the normal location, moving the "future" splanch (also red) to behind the stomach.
6. Time travel occurs, sending original Iki Piki back in time, where he is now "future" Iki Piki. He meets his original past self in the cell, and has the splanch in the normal location (the original one) removed by the organlegger. This leaves future Iki Piki with his future splanch, now tucked behind his stomach.

From the diagram, you can follow the red arrows to see the path of the original splanch. It's removed once from original Iki Piki, then re-implanted into the normal position (shuffling the splanch that had been implanted in the meantime to behind the stomach), where it stays until removed a second time from future Iki Piki after he's travelled back in time. So this splanch is removed twice. Then it's re-implanted into original Iki Piki in the original position, and then shortly after shuffled to behind the stomach, where it stays. And in this scenario, there is no other splanch. Even when the two Iki Pikis are in the cell together, the three splanches in the cell are all the same splanch, just at different parts of its timeline.

Points to note:

• The single splanch in this scenario travels back in time twice. Once in the original position in Iki Piki's body, and once tucked behind the stomach. It goes through the time loop exactly once, then emerges in future Iki Piki, tucked behind his stomach. At this point, the splanch is older than Iki Piki, by the size of the time loop (a few weeks). Iki Piki forever after lives with a splanch that is a few weeks older than the rest of his body.
• This scenario might seem more plausible, but it relies on the surgeons doing a shuffle manoeuvre with Iki Piki's splanches. Why would they, at that time, choose to do such a thing? Would Iki Piki have instructed them to do it, and if so, what's his motivation? What if they just choose to do the simpler thing and stick the new splanch behind the stomach, without moving the other one? Does that force us back into scenario 1?

Well, that all seems pretty straightforward now! If only some future strips would complicate the story some more...