Recovering the past

One of the themes of current scientific progress is getting more and more information out of tiny amounts of data.

But the other theme is the selection effect. We call it the Stone Age not because stone tools were the prominent fixture of their lives, but because the stone tools are the things that survive. How much of a caveman's life was spent in a cave? Well, that's the part of it that we can see. We might as well call them "bone people," except every now and then we find a mummy to make it clear there was so much more to them.

And so, like ancient people, it seems like your best bet for persistence is to fall into a glacier.

When my father died, I realized in the last years we hardly ever talked about anything serious, neither before much, he did not hand me over his life experience, advice, philosophy, knowledge, basically the best part of himself. What we have remaining is photos the memories of fun had but that is not the best part of a person.

I realized that everybody who has children owes them to write a book. Dumping everything in it, less-obvious knowledge, experience gained, what worked for me what not, life advice, philosophy, values. Basically an extract of the best part of you, a manual to life, a "what would mom/dad do in this situation" type of book and the best kind of memory left behind, a practical memory, a problem-solver type, not just photos about how we went skiing together.

To put it differently, part of the issue is that when your children realize it is a good idea to listen to you, it may be too late. I did not realize the old mans experience is relevant until my own child was born and that was a week after he gone.

People who have no children but are in any ways interesting or high-achieving should also do this. It would be really better if we had a book from Prathett full of stuff like how he sees the world, values, philosophy, ideas, writing techniques. That way the best part would be preserved.

In the longer run, "uploading" will solve it, but as of now this sounds like a great idea, even better than cryonics, for I am not sure how useful I will be to people 2000 years later when they revive me, but such a mind-extract can be useful for my daughter in 30-40 years. It is selective uploading into the Gutenberg-computer.

There is one sort of information almost everyone leaves behind them, namely the memories of people who knew that person when she was alive. By definition, there is no information theoretic bound preventing reconstructing a person with such precision that everyone who knew her won't be able to tell the difference. Similarly, there is no information theoretic bound preventing reconstructing a person that writes novels which the original version could have written, as far as the readers can tell. So, if we launch FAI tomorrow we can get a version of Pratchett sufficiently close to the original to "fool" his wife, daughter and fans. On the other hand, there might be stronger complexity theoretic bounds: reconstructing a person to fit a given set of "output" is a problem which is a priori only known to be in NP.

Previous discussion on a similar topic here:

http://lesswrong.com/lw/1ay/is_cryonics_necessary_writing_yourself_into_the/

This recent blog by Scott Aaronson seems relevant

One of the themes of current scientific progress is getting more and more information out of tiny amounts of data.

I think that if the universe was once a single spot and everything we see comes from there, then the information about everything is everywhere. If we had knowledge of the mechanics and enough computing power we could understand what has happened in the universe since the start just by observing the current state of one atom.

This is because, if we could measure them with full precision, the current position, direction, and speed of an atom (and all other measurements if we could do them physically) are only possible with one and only one specific history of everything else in the universe.

...to what extent can people be re-created from what they've left behind them...

I think us or any other intelligent species that continues after us will control every aspect of our environments. Just like now we are starting to understand the full "language" of DNA and we are in the first steps of cloning, AI, etc., we will also control the planetary weather, solar system level direction and orbits of planets, etc.

In this context it will be very easy to replicate past living beings. The problem is that because they will be operating on a different set of materials (h2o, salts, carbon, etc.) it will not actually be that original person even if it's an exact replica.

Unless there is some sort of entanglement possible, I think that If a person is copied, the copy is not the original person unfortunately, so when we die we will not be back unless its on the same set of materials, which is possible, but very improbable.

EDIT: The above phrase:

This is because, if we could measure them with full precision, the current position, direction, and speed of an atom (and all other measurements if we could do them physically) are only possible with one and only one specific history of everything else in the universe.

Replaced the original sentence:

This is because the current position, direction, and speed of an atom (and all other measurements that can be done physically) are only possible with one and only one specific history of everything else in the universe.

To reflect, as observed in the comments below by lesswrong.com/user/asr/, that "You can measure those things to only finite precision".

If you want to jump into the deep-end of the sci-fi pool, it's convincingly arguable that with a complete enough grasp of the physical laws, and sufficient processing power, you can reconstruct a past state up to Xs into the past and with Y% accuracy. (Of course "accuracy" is a pretty arbitrary measure).

For example, using the current trajectory of a baseball, it's fairly trivial to deduce where it came from 1.5 seconds in the past with, say, 99% accuracy. Now just extend that process to the entire Earth. It would be earth-shatteringly difficult, of course. And of course there are a hundred and one open questions about the nature of consciousness, whether a person reconstructed in such a fashion would be the "same" person, and of course the problem that describing a system isn't the same as reconstructing a system in reality.

But it's not impossible given our current understanding of the universe.

EDIT Somehow I missed the above post. Which covers all this.