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Judging from the reader responses to my last essay, if Erwin Schroedinger published his thought experiment on the EPR Paradox today, he'd have had the Cat Protection League breaking down his office door within minutes.

Am I just on the receiving end of a massive selection bias effect, or are people today really that incapable of handling metaphor, let alone the idea of a thought experiment?



It reminds me of an ethics class where the professor asked "if there was a pill that would make you perfectly moral, would you take it?"

The discussion collapsed into redefining the question instead of reflecting on the possible answers.


"Testing by unsupported meat puppet seems a little pointless."

But that's what makes it fun. I only read the first few comments when I first read the post, things seemed to be going well. Usually don't see that level of goofiness around here.


Remember, some of your readers may believe that even acortical meat probes come equipped with an indwelling ghost which is dear to their big, invisible, friend.

This is a common belief among many, so they can't be faulted for having picked it up, but neither can others of us be faulted for thinking that it also increases the level of their relative kinship to acortical meat probes. (Much as I can't shake the feeling that some Owners are anti-abortion because a fœtus is at about the level of self-direction and non-{work-related} intelligence they'd prefer in their employees, constituencies, and parishioners.)


FWIW, some people got it.


Honestly, I thought it was brilliant. A wonderful thought experiment and a reminder of the "Thermo-dynamic miracle" that is life as we know it. Brought to mind Richard Dawkins "To be Read at my Funeral"

"We are going to die, and that makes us the lucky ones. Most people are never going to die because they are never going to be born. The potential people who could have been here in my place but who will in fact never see the light of day outnumber the sand grains of Sahara. Certainly those unborn ghosts include greater poets than Keats, scientists greater than Newton. We know this because the set of possible people allowed by our DNA so massively outnumbers the set of actual people. In the teeth of these stupefying odds it is you and I, in our ordinariness, that are here.

The hard science a lot of people argued in the thread gets a bit deep in it for me, but the notion behind it, the idea that to be at this moment, at this instant, in this existence, able to be aware of what has come before and cast eyes to the future, is pure in it's wonder.

Besides, meat probes just makes me giggle.


hmmm... maybe not every reader of your blog really knows what a Gedankenexperiment is?


It wasn't going all that badly until Instapundit linked in. After that, yes, it did start to look a bit like a proof that Earth IS currently survivable as a decorticated meat puppet.


There has been an annoying trend towards increasing literalism these days, or so it seems to me. My theories on why are all at the "raving moonbat" stage of development, though, so I'll decline to air them.

-- Steve


If people reading the blog of a Science Fiction writer can't handle speculation, on a theoretical probing of theoretical planets (or our own in a theoretical past state, then it's a wonder that they read Science Fiction at all!

And yes, there are tons of folks who can't handle metaphor and can only process it as something other than literal if you hold their hand through the process, and then they resent you for making them feel unintelligent. Thus the popularity of reality television.


Actually, I am reminded of a fun little yarn ...

Allegedly, some postdoc physics researchers at a certain university were sitting around in a pub one evening and ended up kibbitzing on a discussion at a neighbouring table, between members of a local Animal Rights group.

So they began discussing, loudly, how they were taking delivery of the cats for the Schroedinger Experiment that week, and they were going to get through fifty cats in order to test the hypothesis. And they'd spent all day moving the animals into their cages on the second floor of the Physics Building.

The next night, someone broke into the aforementioned building.

It was only one story high ...

11: that what is was, a thought experiment?

Would have done better with Marvin the Robot. "Where is that stupid probe taking me now, and why is he so interested in these conditions. They're so boring."

One of the interesting questions you didn't deal with is that an Inuit family can make a living on the tundra and pack ice, a !Kung family can make a living in the Kalahari, and people have been farming the mountains of Papua New Guinea for ca. 30000 years. But industrial civilization can't live off the land in any of these settings, and requires massive inputs from elsewhere.

I'd say that this does not augur well for civilization doing well on any life-bearing planet, including our own. Maybe the probe is the problem with the thought experiment, not the puppets?


heteromeles: I assumed, being naive, that opening an essay by saying:

(Pay attention at the back: this is a trick question.)

[ intro paragraph ]
Why is the Earth uninhabitable?

Let's play a thought-experiment ...
Might have tipped everybody off that I was playing a, well, a thought experiment.

But obviously I wasn't unsubtle enough in flagging this as a thought experiment.

PS: the !Kung and the Inuit come with a lot of cultural and technological baggage for dealing with their respective niches. But we may equally well say that a meat probe packaged neatly in a space suit would find the Moon hospitable. I rigged the experiment deliberately to look for hospitable environments, not ones that are marginally inhabitable if you've got a body of knowledge and suitable equipment.

A corollary to this thought-experiment would be: how much do we still need to learn before we can design a minimal biosphere that can support human life without any inputs other than energy? ... But that's a topic for another essay.


While many appear to have missed the point by a margin best expressed in astronomical units, there was some interesting discussion (I'm in the mid-40s on the comment thread; if it gets rapidly worse from there on in, I don't know it yet).

I gather the discussion didn't go in the direction you'd expected, but I'm still learinng a bunch and various comments are making my neurons go "huh." Not a total loss, by any means.

Besides, why would your comment thread be immune to Sturgeon's Law?


Dan: Dunno, I ought to know better by now. I guess I just keep hoping that Sturgeon's Law will serve me up some caviar.


Gotta disagree with you on the technological baggage: I picked those two precisely because they could get 99% of their needs from their local environment (yes, there's a question of how far suitable stone circulated in the Arctic, but that's the only problem).

The bigger problem is that it wasn't really a thought experiment. The point is true: leaving out the cyanobacteria, there is a low probability that joe random organism could be picked up, put somewhere else in space and time on Earth, and survive for 24 hours. It's called niche theory, and humans are actually pretty far up on the survival percentage curve compared to most species (which are parasites, and can't survive without their hosts). Granted, we suspect that most organisms are actually bacteria in the deep crust, so if you incorporate that cththonian territory, it changes the stats dramatically. Perhaps we should just leave this to surface dwellers?

Problem is, I've been doing some reading on this too, and I'm not sure it's possible to determine when the Earth had human-survivable atmosphere to the nearest 500 million years. That's about the margin of debate about how long it took for the cyanobacteria to win out and establish an oxygen atmosphere (vs. one of sulfides and/or CO2).

So, leaving aside the unknown 500-1 billion years of future Earth, we're left with saying that Earth was crudely human-habitable somewhere on the planet's surface for between 10% and 30% of its history depending on which scientist you believe and which geologic strata you study. That does play into stories about finding interstellar life, but it's much more complicated.

So yes, it was a thought experiment, but the details got in the way. Or maybe we're just out to annoy you.

Additionally, you're dealing with numbers that are on the scale of the US war budget, and people don't think well on that scale, as we're demonstrating right now. Veering into politics, AFAIK, the biggest effect of the Great Recession is that politicians are no longer ashamed of talking about trillion dollar deficits, and arguments about whether it takes $500,000 or $1 million/person/year to keep a US soldier in Afghanistan are seen as political spin efforts rather than "holy crap, why are we spending so much on this war?"


Thought experiment? So that makes what you described a thought crime. I do believe the trend is towards punishing thought crimes, yes.



h: terminology fail. The Inuit and !Kung are heavy users of specialized techniques and equipment and knowledge neccessary for surviving in their environments -- technology, in other words. It's not made out of titanium alloy and semiconductors. In fact, it's 99% sourced from local, naturally available items. But that in no way makes them a non-technological civilization (unless you define technology purely as "engineering developed since 1800").


I've run into this as well, especially among science-minded SF fans. Some of whom take an odd delight in deconstructing the premise of the novel they just read in order to underscore just how completely implausible it really was. I know at least one person in that category who is fundamentally incapable of taking any presented problem at face value, and simply has to attempt to redefine the question in some way before answering. These are the people who answer this question:

Q: If you were stuck on a desert island with one other person, who would that person be?

A: One with a satellite phone with solar charger, and a solar distiller for water.

And they take pride in this. It seems completely implausible premises offend them somehow, and they take pleasure in answering the question as asked not as implied.

The trick is to somehow get past their smug bloody literal mindedness and engage their 'What-if' brain (if they have one, the redefine-the-question person I mentioned didn't seem to have one as far as science was concerned). I've only managed to do this in person. On the web, it's a heck of a lot harder.

So yeah, you got both ends of the stick there. Selection bias in favor of people who can't handle a metaphor without deconstructing it.


1) Of course you are on the receiving end of a massive selection bias. That's true for every posting, though. Only those moved to respond, respond.

2) I'm convinced that habitual TV watchers have less ability to handle metaphor. This one I don't have any evidence for, but I believe it anyway. My belief is that their thoughts are shaped to fit between two sets of commercials. The deficit in handling metaphors is one of many consequences of this. It's also true that TV prefers to show action rather than describing it, so metaphor is much less used than it was. This means that people have less practice in using it.

Of the two, I suspect that the selection effect is the more significant, but I'm convinced that both effects are present.


Totally off-topic, Charlie:

In the last two days I've seen two online overviews of H.P. Lovecraft and the Cthulhu Mythos. In each of the ensuing discussions, someone has rapidly chimed in to list 'A Colder War' as one of the quintessential stories of the Mythos. You should be proud.


Clifton, off-topic is fine.

(Did I say that I'm currently waiting for the copy edits on "The Fuller Memorandum" to show up? And that TFM is distinctly darker and bleaker than "The Atrocity Archives" or "The Jennifer Morgue"?)


@17: Charlie: agreed on the term divide. Of course we can then argue about whether "hospitable for humans" can be disentangled from normal human behavior, which includes toolmaking, tool use, and environmental changes such as building shelters and setting fires. For example, using a shaved polar bear as a test for habitats suitable for polar bears would be seen as silly, and not letting an ectothermic lizard move around to find the appropriate temperature would result in a lizard that didn't survive very well.

Of course, we do like annoying you.


@21 Shiny....for certain dark and morbid values of shiny... How long does it normally take between copy edits and hitting store shelves?


Tetragramm: it's due out at the beginning of July on both sides of the Atlantic (Orbit, UK, in paperback; Ace, US, in hardcover unless they change their minds and run it as a trade paperback).

But there's a Laundry short due on over the fester -ive season.


For what it's worth, I liked the thought experiment, but the first 20 or so comments of people completely missing the point put me off reading on and commenting myself.

For all that it's a revolution as a communications medium, people "on the Internet" sure don't seem that good at communicating most of the time.

Or maybe it's just the global effect, the point concentration of idiots can now far exceed that ever achievable before.

Eagerly looking forwards to TFM coming out. :)


I wonder if most of the comments were about the experiment rather than the conclusion, simply because it was so much of a "well, duh" statement. Or maybe that was just me.

It just felt like you created a convoluted and elaborate structure to argue something that was obvious. But then I claim that New York/New Jersey isn't really suitable for human habitation; wind chill take perceived temperatures down around -15F in winter (despite being almost as far south as Madrid); heat factors take them up to over 100F in summer. Definitely not the moderate London temperatures I'm used to! :-)

As a young kid, I remember reading how building submarines requires surviving harsher conditions than spaceships... a spaceship merely needs to handle 1atm pressure differential; a submarine may encounter much greater pressure differentials than that!

So, since there was no controversy about the conclusion all that was left to common on was the thought experiment itself.

Just a thought. Maybe I'm overthinking.

(I'll claim the moral high-ground; I didn't comment :-))


Can't stop people from disagreeing with you. The internet is a great medium for opinion, informed or not.


I like to argue that the reason I prefer living in the tropics is that it's the environment I evolved for.* Water in solid form? Puh-lease, that's for drinks only.

[*] Of course, this ignores my problem with severe melanin-deficiency, but in other respects...


Corwin: These people are lawyers, not pioneers. Their longing for and inability to self generate a sense of wonderment is evident in the contempt they heap on anything and everything in the genre. They may not be evil, but they're soulless zombies. Chuck some Larry Niven novels at them to slow them down and SAVE YOURSELF.

Charles: The response should have been somewhat expected. You hit the radar on several popular websites (bOING bOING, Slashdot...) so all sorts are reading your blog. Barnacles.


@18 Corwin: you mean that a thought experiment isn't about who you'd want to survive with on an island, but some sort of popularity contest about which attractive celebrity you'd like to boff for a few days until you both died of dehydration? Personally, I'd prefer to have my partner on the other end of the satellite phone line organizing the rescue mission, and someone I can happily survive with to pass the time until said rescue mission gets there. Guess I'm definitely in the soulless zombie category.


I think everyone was distracted by the arbitrariness of the scenario. Why would a civilization that could send a robot probe care if they could survive on a random location on a planet, with no technology, and no brain? Sorry, it's not a very good premise.


Tim @ 31: Have you read "A Gift from Earth"? Anyway, the point of a thought experiment is to highlight a specific something in order to render an understanding. It's not about practicality. Often (usually) thought experiments postulate impossible set-ups. This is done with FULL UNDERSTANDING by the thinker that the set-up would never fly in the Real World. The set-up of the experiment (Meat Probes) is not the point. So, no, not everyone was distracted by the arbitrariness of the experiment. Only those that don't understand or cannot get into the spirit of the thing. Have you read "Ringworld" Tim? You might like it.

Charles, I apologize if my sarcasm offends thee.


Craig@32 - I'm not sure if you're using Ringworld as an example of a thought experiment, but there's a good parallel here; people were critical of the science of Ringworld (eg inherent instability). Hmm, the wikipedia page adequately summarises it so I don't have to retype :-)


Stephen @ 33: Usage is sarcastic. See my post @ 29.


Craig@34: Sarcasm or not, the response of people to Ringworld (almost wrote Discworld!) was similar to the sort of response Charlie had to his thought experiment. It made an interesting parallel.


Stephen @ 35: Both references to Niven books were as parallel as possible (and yes I was thinking about the geek response to the original Ringworld), but that was not really the point I was after. Hmm. The meta is getting thick around here...


Hi. I didn't comment, but have to agree with Tim@31. Phrasing the thought experiment with decorticated humanoid probes WAS a bit distracting. Why not just use cats, instead? It worked for Schroedinger.

Gary Snyder wrote "We could live on this Earth without clothes or tools!" But he did not say "without brains".


You were proposing bombarding the planet with brainless clones. This is a bizarre and funny idea, and of course people are going to grab onto that and run with it. (Plenty of people make cat jokes about the other experiment as well, as you surely know.)

Your main argument, however, is roughly "Not only is the universe hostile to human life, but so is the Earth!" This is not really likely to spark to much discussion. The fact that Earth is not actually that habitable without tech is not really surprising. Heck, you're Scottish - you should know this.

The Cat Gedanken Experiment is timeless in part because of the vivid imagery, but mostly because the conclusion is mindwarping.


The whole meat puppet thing seems beside the point, at least the points that I got from it. That is, given a random sampling of 'Earthlike' planets, the likelihood of coming across them at the period that thay would be habitable (by 'life as we know it') is very slim. And that we are here at this moment because we couldn't exist in any other era, in other words, looking at the whole of Earth's past and likely future the planet has a rather small window of habitability. No anthropic principle hooey necessary.

I think the idea of a probe that's dense enough to drop humanlike samples in an ocean shouldn't be taken too seriously.

As for people not getting metaphor, the fundie/creationist types show that there are plenty around. Just try telling them not to read their scriptures literally.


I dunno, I liked the meat probe idea well enough.

Of course, when I start speculating on whether or not the meat probes stuff random material in their mouths that's just me taking the thought experiment and running with it.

An environment in which nothing will kill you if you eat random parts of it is a more demanding standard than an envrionment in which nothing will kill you as long as you don't eat random parts of it, after all.

However in either case it occurs to me that you'd have to drop lots of probes per planet to make sure you hadn't missed the--comparatively small in percentage of planetary surface, but still potentially quite large in square kilometers--habitable zones.

And if the habitable zone is quite large in square kilometers, does it really matter that it's quite small in percentage of planetary surface? I guess it kind of depends on what you want the habitable zone for.


I just wondered if you'd been reading some of the stuff saying James Cameron ripped off Poul Anderson. Add an uplink to your meatpuppet so it can be controlled from orbit and you've got Call Me Joe.


I only skim read the comments, but I'd put it on selection bias. Mostly it was only people who were taking it literally who took the time to respond. Which is always the way....

My comments on the metaphorical thought experiment: Personally I think that using the meat probes made sense, it allows you to see what happens when, say, a young of the species experiences technology fail. Which is always good to know if you're planning on moving in!

Also, the habitable zone in time and space may be pretty small as an overall percentage, what's worse is that it's going to be distributed over the whole galaxy. At any given moment there will probably be a habitable area you can utilise, it's just really really unlikely to be anywhere close to you.


To quote Lazarus Long 'never underestimate the power of human stupidity'.


And theres another example. I was answering your original post, as I completely agree, but in my haste/ire I forgt to pay attention so please, I was not trying to upset anyone(something I find overwhelmingly easy)just stating a base rule people should keep in mind when dealing with (or watching the antics of)homo,so called, sapiens. As a previous post stated your blogs and comments are usually very interesting, but so far, not being particularly academic or tech minded I have been (my friends would be suprised to hear) intimidated by the level of response.


There is a corollary set of information that you get out of the meat probe data. Not only do you find out to what extent a given planet is human-habitable, but you also get a statistical profile of what environments for which we are best adapted. (most likely temperate coastal regions with moderate flora & fauna populations and low seasonal temperature variations).

You bomb enough planets with meat-probes and you will gain a very detailed knowledge about what conditions we can survive.

Also, don't let the literalists get to you. A friend of mine calls this problem "engineer's disease". Basically people with black & white/right & wrong viewpoints don't deal with abstractions very well. They saw your delightfully gruesome thought experiment through literalist detail-oriented eyes. The internet unfortunately is a fertile ground for their deconstructive obsessiveness.


Mark Jolliff @44 I have been...intimidated by the level of response.

You're not alone. Often the discussion here gets over my head (more so at Ken MacLeod's blog). I try to contribute, but sometimes feel like I'm stating the obvious, I suppose someone has to. Good thing about this internets thing -it's easy to look stuff up.


Tim M.@45 - I like that idea, drop colonies at more or less random with minimal tech support. Come back in a couple of millenia and see what's happened.

Hmmm. Although that is close to what the Eschaton did in Singularity Sky/Iron Sunrise. Time for a re-read, I think... :-)


It was like the sound of a thousand people suddenly missing the point and then endlessly going on about it...

On the thought experiment itself: Picking humans as your test then insisting they must be able to survive sans-tech is quite limiting - using tech is what we do. It's our survival skill.

We aren't remotely designed to survive without supporting tech. Without some sort of minimal clothing both sexes frankly struggle to sprint without things flapping around (let's not dwell on that).

But, more fundamentally, yes - it's your thought experiment, so you set the rules. And in any case it's just a thought experiment - to read some of the posts on the other thread you'd think you were advocating it as a policy.


Agreeing with 48. Without some kind of local knowledge and a degree of tech support we haven't been able to meet the criteria of your thought experiment since we were kicked out of Eden and it could be argued that even there we had a large degree of support, though apparently not enough.


Charlie@12 supposing we had the tech to create a biosphere capable of supporting human life with no other inputs than energy ( which I take it we could get by building a 'large' fusion reactor and then removing the containment field which I posit will be easier) then would that make us gods?


Charlie, it seems like a lot of your hair-pulling came from single posts made by drive-by commenters. You could probably make your blog a more thoughtful place if you set up sign-in system specific to this site, like a bulletin board. Most of your regular visitors use a standard pseudonym already. I assume that you don't want the hassle of running something like that.


It could have been worse, Charlie. Instead of "meat probes," you could have written "babies."


Ref 38 and 39, as far as I could tell, a number of people in the previous thread did not seem to agree about the habitability question or even get the basic concept. "I live on Earth, therefore Earth must be habitable, QED this is soo soo st00pid WTF BBQ."

I was wondering how much of the habitability-over-time consideration was triggered by the "deep time" thinking done for Palimpsests


Madeline: "babies" was the original idea.

(An environment can probably safely be declared human friendly if an 18-month-old -- at the crawling/babbling/putting-stuff-in-mouth stage -- can survive 24 hours in the wilderness without dying.)


@Charlie: I assumed at much. At least, I thought that was made fairly clear. But if people had trouble with "meat probes," I can only imagine what the backlash would have been if you'd said "infants" outright.

These people must really hate Jor-El.


An environment can probably safely be declared human friendly if an 18-month-old -- at the crawling/babbling/putting-stuff-in-mouth stage -- can survive 24 hours in the wilderness without dying.

The key technological fix for this is "Mum". (I recall you being quite loud, and entirely right, about this and its upshot for the sex politics of science fiction on the High Frontier thread.) As a species, our young require a long development stage with the support of others (not necessarily parents, but people who fulfil that role and those of grandparents, peers, etc). I doubt modern Yorkshire is habitable on this basis; the 18 month old would have had a good chance of crawling onto a road and being croaked by a vehicle of some sort. Modern Islington certainly is, but only because a social technological primate would intervene before an iron-based carbonic entity did, and the vast majority are benign.

There's a reason why a small child wandering off causes people to freak. Do you see why I have problems with the set-up of the thought experiment? Even in industrial civilisation, a child at the same stage doesn't have great chances without the support of society.

Actually, this is a good point that arises from the earlier post; not only is habitability determined by technology, it's determined by society.


Tim@47 wrote: "... drop colonies at more or less random with minimal tech support. ...that is close to what the Eschaton did..."

My impression is that the Eschaton designed and dropped colonies carefully. A lot of them had a mix of only a few languages/cultures, and the tech support given always seemed to be sufficient. I believe the original colonists of the Heptagon (Septagon?) asteroids were given a year's worth of air and supplies, and CORNUCOPIAS. (It's not clear that all colonies were given cornucopias. They could have been, only for some colonies to lose theirs in civil wars.)

Charlie could write an interesting story in an early Eschaton setting, if he didn't have any better ideas... : )


@2 mea culpa - I should have accepted the limits of the experiment. I was trying to highlight the (instinctive?) separation of humans from an ecosystem (or artificial equivalent) when we can't survive independently in the long term any better than a severed pinkie. but then again many autotrophs would probably do well in an environment capable of sustaining something as fragile as a human. oh well.


@2 mea culpa - I should have accepted the limits of the experiment. I was trying to highlight the (instinctive?) separation of humans from an ecosystem (or artificial equivalent) when we can't survive independently in the long term any better than a severed pinkie. but then again many autotrophs would probably do well in an environment capable of sustaining something as fragile as a human. oh well.


I liked the thought experient, but it honestly made me think you validated the idea that its damned hard to find any planet that is hospitable to any life let alone evolve something intelligent. I keep reading that it must be inevitable that there must be intelligent life out there simple becuase of the shear number of stars in the universe, but I really wonder.


I'm often reminded in my daily life of the fragility of our bodies, the fact is even simple movement contains a high potential for injury, even lying down can cause damage without constant attention to discomfort/posture, as the fact that keeping tetraplegic patients alive is a non trivial issue proves.

So to be fair your meat puppets (Or babies) aren't really very good at surviving anywhere at all. But I understand that harping on that is kind of missing the point...


@61, Todd M: Well, the constraints for life are a bit broader after all, as was pointed out numerous times in the other thread. Intelligent life is a whole 'nother ball game, and unfortunately we just don't have enough data to say anything about that, nor are we likely to at anytime in quite a long while, I'd say. It could be that a lot of things that people point to and say, "Yes, that's important for us to exist" are actually neutral or harmful for the evolution of intelligence (in the long run). Or of course it could be the opposite. We just don't know.


The unexpected point of the previous thread -- that such a small fraction of the self-selected sample seemed to under stand gedankenexperiment [Etymology: German, from Gedanke thought + Experiment experiment. Date: 1941. : an experiment carried out in thought only ... Merriam-Webster]. Well, I learned that painfully through decades of teaching teenagers through 90-year-olds.

I was trying to side-step that by suggesting that it might matter that organisms and planets co-evolve, but that almost made me look as if I didn't know my own teacher's teacher's teacher, Albert Einstein, God-Emperor of Gedankenexperiment.

In another thread, long ago, I'd given a more extreme but less biological gedankenexperiment. Determining the structure of a galaxy by scattering a coherent beam of a few billion neutron stars through it. Of course, a neutron star laser leaves the galaxy rather dicombobulated afterwards, but hey, the experimenter gets the intended data, to very high resolution.

Similarly, I'd tried to get my colleague Stewart Nozette (now in rather deep espionage trouble) to modify Star Wars hardware (this was when Clementine was on the drawing board) to scatter a million 1-square millimeter devices on the surface of Mars. Each would measure one thing, and microactuator wiggle a micromirror. A laser ion orbit would scan the Martian surface, pick up the coded mirror wiggles, and have high resolution mapping of what the micro-sensors measured. Or should I admit to my having been on the Stewart Nozette payroll, in a nonclassified NASA-University-Corporate conference on Manned Lunar and Mars exploration, held at Disney's Epcot Center? My wife was included. It's public record. He's still in jail, due to "flight risk" -- and WTF was he thinking? Should have left leaking state secrets to Israel as a -- that's right -- gedankenexperiment!


On the Internet, Nobody Knows You're a Dog Cat.


On the wording of the thought experiment I wonder what would have happened if you'd said 'clones of Paris Hilton' (or any other pointless celeb).

I too was overpowered by the technical posts, my bio/geo -ology skills are nonexistent.

I'm also quite happy with the idea that there is only one sentient species in the galaxy and that it's all down to luck. An incredible amount of good fortune that we really should be happy with.


"...he'd have had the Cat Protection League breaking down his office door ..."

Taking sides again, Charlie? What about the SoV Protection League?


I rather suspect that some "people" (including the couple behind me on the streetcar this morning) actually are the aforementioned APMs.


capable but not necessarily preferable literal literary different dots connect to form different fabrics from material to immaterial comforts and leaps some imprinting ensues.


Stephen @ 26:

"It just felt like you created a convoluted and elaborate structure to argue something that was obvious."


Furthermore, by assuming a poor probe design, Charlie forced the conclusion. He's right, but the fact that his poorly-designed thought experiment agrees with reality is mere coincidence.


Madeline@52 & Charlie@54

I've always understood that the ancient Spartans would leave their babies naked and unprotected on a hillside overnight. If the infant survived it was good enough for Spartan society, if not, well.. try another planet.

Unfortunately I can't immediately find any evidence to back this story up. Certainly 12 year old boys had to fend for themselves for a year in the open with nothing more than a single garment and a knife - but I think that's suitable technology, and doesn't count in this thought experiment.


There's an interesting physics vs. biology culture clash bubbling merrily away beneath the surface here. The issue is that the gedankenexperiment is more revered in physics, because in biology, particularly in ecology, the answer's typically "it depends" and you have to specify the conditions so exactly with meat puppets or whatever that the point gets lost in people whining about how arbitrary it is.

The culture clash is that there's this unspoken assumption that physics is the queen of sciences, and us scruffy biologists should doff out hats to our betters and play by their rules. This was true up through the space race, perhaps. Nowadays, physics majors go into the finances and biology majors go into high tech startups, if they're not off trying to save the world from the mess caused by the hard science majors trying to improve things that they didn't understand.

Anyone who doesn't think there's a culture clash should look at who the Creationists go after. It's evolution. Why? The theory of evolution has stood up to reality far better than anything the cosmologists have cooked up. I mean, allegedly we don't know what 96% of reality is, yet the bible thumpers go after the biologists over what happened on Days 5 and 6 of Creation, and the physicists get a free pass on the first four days, even though their explanations are far less bullet proof. That's cultural bias. You go after the apparent underdog.

Anyway, I still have to put up with BS from people with physics degrees bloviating about how, because they have a degree in physics, they therefore know everything worth knowing about my particular field. They're usually wrong, and they're usually quite upset when someone demonstrates how wrong they are. That's culture, not reality. It still doesn't stop them from, oh, attempting to design carbon collectors that work better than real trees, for example, without looking at real trees for design ideas.

Charlie, I know your background, so here's the question: why play by the rules and culture of physics? That's the old regime.


I'd think that putting a bunch of chimpanzees down on the planet would serve a similar function.


heteromeles @71: because I'm still working on the frame for the next thought-experiment (the one about how many organisms it takes to sustain a self-contained biosphere that can support human life with only a reasonable[*] energy input to keep it ticking over).

[*] I'm talking sunlight-equivalent for photosynthesis, not gigawatts so you can play tricks with electrolysis or Fischer-Tropsh synthesis.


Todd M @60, I don't think that it's so much that life (or a habitable environment) elsewhere in the universe is unlikely, but that the likelihood of coming across it at the right moment is small. There very well may be a lot of life out there, but we'll never know.

Adrian @70; Don't know about the Spartans, but you remind me of a silly bit of Stapledon's 'Last And First Men', where the city/tower culture drops infants from one plane onto the wings of a lower one, and whether the baby holds on determines its fitness.


@ 71 - you beat me to it, but ... The Cretinists are amazingly literal-minded, and usually stupid, but not all of them. Some, like THIS loon are intelligent, but determined NOT to follow conventional learning. And logic-chop, and be a real pain. However, they don't go for the physicists for a very good reason. Biology apart, the real killer to any cretinst is the raidioactivity decay-equation(s). There is NO WAY around that one except by shouting very loudly, trying smoke-and-mirrors, and lying. And even then, it doesn't work - and they know it.


@71: There's some merit in this comment. As Chad Orzel said in another venue: "To me, one of the most delicious things about computer science is the way it turns the traditional 'pyramid of sciences' on its head. We all know, of course, that math and logic are more fundamental than particle physics (even particle physicists themselves will, if pressed, grudgingly admit as much), and that particle physics is in turn more fundamental than condensed-matter physics, which is more fundamental than chemistry, which is more fundamental than biology, which is more fundamental than psychology, anthropology, and so on, which still are more fundamental than grubby engineering fields like, say, computer science … but then you find out that computer science actually has as strong a claim as math to be the substrate beneath physics, that in a certain sense computer science is math, and that until you understand what kinds of machines the laws of physics do and don't allow, you haven't really understood the laws themselves … and the whole hierarchy of fundamental-ness gets twisted into a circle and revealed as the bad nerd joke that it always was."

I'd commented:

The assumptions of Reductionism are more deeply flawed than the anomalies given. For one thing, as Philosophers of Science have argued, there's the implicit but unjustified assumption that there is ONLY ONE REAL WORLD. Is one assumes that (usually implicitly in one's Kuhnian paradigm) then one falls into the trap of kludging together a metric for the "distance" between one's pet discipline at that putative unique real world.

The unjustified metaphysical assumption is usually made that there is, in total, ONLY ONE SCIENCE (meaning set of all science disciplines) that describes the putative unique real world.

I've discussed at length with Geoffrey Landis the possibility (which would seem to make some fun Science Fiction) that we meet the extraterrestrials, and, even after years of effort, cannot understand their science or technology, nor they ours, as both of us have something that works, yet is intrinsically irreconcilable.

By the way, in teaching a history of scientific revolution course to several hundred adult students over the years, I first gave a quiz, and then again at the end, which plots metaphysical stance. Returning the first quiz, I point out that before Kuhn, essentially all scientists would have answered "true" to each of the 10 questions, and Kuhn himself answered "false." Indeed, the quizzes were never all "yes" nor all "no" in this class, and tended to skew more Kuhnian after I presented Kuhn and Lakatos and engaged in a week of conversation with the class.


Hmmmm... I would go so far as to say the hyperbole is patently obvious in the original thought experiement.

Indeed here on earth we frequently sacrifice animals to test things out before we put humans in the hot seat or move a drug to clinical trials. Even then we can't be sure something is safe until people kind of um... don't die. Putting a brainless meat puppet in harms way, for the good of thousands of colonists, suddenly seems extremely plausible and useful. I'd go further to say, if we had the capability and no more or less ethics than we do today, we may do exactly that.

OK using the homind-spam approach and dropping canned human all over the planet and observing the death rate is a kind of not how we'd do things BUT:

It would be the kind of a behaviour of an intellegence that emerged from a hive mind, like a ant-colony or bee-hive, that considers it's hive drones an expendable resource. It clearly would not value the lives of an individual. Who's to say what a sentient space probe might think is a good idea?

I think the whole set up might make a good sci-fi short story.


Look at it this way: The pampered elite of the Europe and the US are increasingly suffering from a peculiarly prevalent disease of the self righteous, Humor Deficiency Syndrome.

What was it your fellow countryman said? “O wad some power the giftie gie us, To see oursel’s as ithers see us!”

Good luck with that.


Charlie@73 Since the Biosphere 2 experiment the answer is 'A damned sight more complex than we ever realised' Ecology is still in the 'secret of tool making is to bang the rocks together guys' level of understanding. Not surprising really, working out the relationships and interactions seem to follow the same sort of maths as the travelling salesman problem (is this np complex? higher maths is way beyond my usual event horizon).


It could have been worse, Charlie, you could have had a horde of drive-by commenters giggling about the phrase "meat probe".


@73: Hi Charlie, the answer you want is "your worst nightmare times two." Anyway, if you want photosynthetic area, you can model a canopy of photosynthesizing plants as equivalent to a single leaf of the same size, to a fairly high degree of accuracy.

The problem with this approach is that it doesn't take into account the needs of the "brown ecosystem" where nutrients are being broken down and nutrient pools are lying around waiting to be used, because the nutrients can only be used in particular proportions (see Redfield ratios). This is where the math gets, well, ugly (hence the worst nightmare times two rule). Have fun.

@79: I had that discussion about the state of ecology with another ecologist a few years ago. There's this physics-inspired desire to find "The Laws of Ecology" which will make it all simple. So far as I can tell, these Ecology Laws don't exist, any more than there are Laws of Computer Science that will allow you to create any arbitrary network of programs to work perfectly every time. We know a lot of "laws." Every single one is conditional, and the problem is figuring which ones are relevant to a particular set of conditions. Physicists run into the same problem when they start dealing with quantum mechanics and gravity simultaneously.

I'd say the real problem is that ecology tends to be more of an explanatory science than a predictive one, and that's because the experiments are typically too huge and too long to be fundable by normal funding agencies, who favor three year granting cycles. Since ecologists prefer to have lives, families, and money, they tend to do the easier, explanatory studies. Still, the science goes forward regardless.


@81: I find it quite head-scratching that there's some kind of physics-inspired desire to find 'the Laws of Ecology' at all, as it has been my (admittedly rather incomplete) observation that the utility of such things rather rapidly decreases as you get more and more complex systems. Physicists can get by with using all sorts of simplifications (spherical cows moving in simple harmonic motion...), but for chemistry, and still more biology, and still more ecology, or psychology, or sociology, or anything else involving loads of very complex non-statistical systems interacting, that sort of approximation is no longer particularly justifiable or useful. Even physicists acknowledge this; look at how many stellar models take into account all the physics we know that could be involved, for example (hint: not many--even given the incompatibility of quantum mechanics and general relativity), or for that matter models of any reasonably complex system.

The reason, of course, that physicists believe that there must be something underlying both GR and QM that explains both at the same time is pretty simple: it's happened before. Well, of course there is some back of the brain metaphysics and aximomatic thinking and what not going on as well, but the main reason I see is that unifications have a long and glorious history in physics.

@71: Well, cosmology is a tiny piece of physics, comparatively speaking. There are a lot more condensed-matter people, for example, you just don't hear about them unless they do something like create high-temperature superconductivity. From my very outsider perspective evolution seems a lot more central to biology than the composition and formation of the Universe does to physicists. The former is used to explain a huge variety of observations, just like a very good scientific theory, while the latter mostly has to do with cosmologists and (to a lesser extent) high-energy people. So, saying that physicists don't know anything because cosmologists say that 96% of the universe is not directly observable as it stands (both dark matter and dark energy having been hypothesized on account of indirect observations, of course) has about as much relevance to the mainstream of physics as saying biologists don't know anything since they don't know (for instance) precisely how proteins and other cellular structures interact to drive development, or that they don't have a particularly good picture of abiogenesis. It's not really a concern to the vast majority, or just part of ongoing research.

@JVP: The 'nerd hierarchy' perhaps has some utility as reflecting (to an extent) the 'complexity' of the systems studied in each field, rising from abstractions of much of mathematics to the concrete reality of psychological and engineering systems. It's still not very useful.


Of course, as Charlie pointed out, a lot of this depends on timescale. If your goal is to find a bolt-hole for when your star goes red giant, you might take the longer view and seed with bacteria, then track which planets develop into something habitable for higher life forms. Would that improve your odds somewhat?

Charlie @12 You did indeed rig the experiment. The preamble makes it clear that you are seeking to show that the Earth is uninhabitable and then you set up an experiment to show simply that it is not so fantastically hospitable that a brainless food package dropped at random survives for twenty four hours. This seems to me to be raising the bar somewhat.

It's hard to see how any environment that supports life is not going to have too much competition for a brainless animal, or even a learning machine like a baby.

Though for twenty four hours, it might well get lucky: it doesn't need to eat or drink, after all, and even if it does eat a bad berry, it may well take longer than that to expire. And it will not be exposed to the full seasonal variation of the weather.

I'd have thought you'd want to send fully functional replicants. But challenge them to survive longer than a day: maybe a year. And give them "standard" technology. Our technology is part of what we are. There is plenty of scope for discussion about what technology should be available. As I understand it, a habitation is not the same as an independent colony, so the technology could be supplied from a home base. At least until it is engulfed by its star.

Under these conditions, most environments might well be habitable to a civilisation that has mastered interstellar space travel.

Adrian @70 From memory, the Spartans exposed crippled and deformed babies. This was not a test - just an attempt to keep the gene pool clean (though they wouldn't have thought of it in quite those terms).

Is "meat spam" an accepted term of abuse? Yet?

I think there may also be a cultural bias in the question. In the UK, it is inconceivable that you could drive for a couple of hours from a major city, take a walk in the woods and find yourself face to face with a bear. I suspect that many Americans are a little closer to the wild than the average Briton, and so the proposition that it is inhospitable may be more obvious to them.


@81 From my perspective the hunt for 'the laws of Ecology' arose around the late sixties/early seventies there were several big US (actually Florida Keys) based projects around then attempting to analyse ecological complexity. The only outcome -from a 1980's perspective- was that founding simple ecologies didn't follow the theoretical models at all. Possibly due to the invaders being carried in by birds and fertilised by their faeces. For a more modern example there's a long term observation programme on the volcanic island which erupted out of the sea relatively near Iceland - brain fade I can't remember it's ruddy name- sometime in the eighties which has a similar non theoretical colonisation pattern.

Anyway the Florida experiments yielded the closest to an ecological 'law' yet discovered. At a first order approximation the amount of biomass supported per unit area followed a biomass cubed is proportional to area squared.

Biosphere 2 used some of the insights we've painfully gained into ecology but screwed up due to what I think of as 'engineering bias' or 'gardeners bias' the CO2 problems (due in part, but only in part, to the fact the concrete foundations were, and still are, curing) they had were only the tip of the iceberg. The biomes were planted with a selection from much larger habitats and hence unstable, it would take years to come into balance.Then they added the Biosphereans and introduced several thousand species of microbial fellow travellers into a too small system that was 'coming to terms' with the lack of multi thousand microbial, fungal and insect species to support it's existence, and expected it to work first time!

Sorry hobby horse. Comes of being a biologist and geneticist by training (though not occupation).


I always thought the 'nerd hierarchy' had to do with deployed weapon.

Nukes are terrifying. Chemical explosives are the core of most conventional weapons. Deliberate biowarfare hasn't been practiced recently, thank ghu. Psyops/diplomacy/applied social science most don't consider real warfare at all.

Once biology deliberately creates something really disgustingly horrifyingly violent, it will get more respect. The math thing is just an excuse.

Note that I don't consider this good, just an artifact of human nature.


In the UK, it is inconceivable that you could drive for a couple of hours from a major city, take a walk in the woods and find yourself face to face with a bear.

However, a meat probe deployed thirty minutes' drive West of Sheffield or East of Manchester or an hour's drive North-West of Leeds at this time of year would face a nontrivial risk of hypothermia or falling off a cliff.


@84: I think the desire for ecological laws is alive and well, at least among grad students. It would be nice if it ALL MADE SENSE. I suspect that a similar desire drives people to religion. Or makes them true believers in physics.

In any case, that X^3/2 number shows up a lot. It's also the basis for Yoda's Power Law, which describes how forests self-thin over time (Yoda was a Japanese researcher, and created this well before Lucas came up with Star Wars).

@85: Yes, the weapons hierarchy, which some people also see as the only reason we have a space program (aka peaceful use of missiles, to make sure missile engineers have jobs between wars). Let's flip this hierarchy into reality: --Practical sociology (aka politics) is what causes and prevents all wars. --biowarfare is impossible to control once let loose, which is why anyone who knows anything about the plague, smallpox, or the depopulation of the Americas stays damn far away from that stuff. --chemical warfare is similarly hard to control, aside from the explosives. --physicists make bombs (working with chemists), or nukes, which are most useful as high status threats for negotiating purposes.

In any case, you can destroy civilization with enough nukes, or something someone cooks up in their lab and has a mistake. If you want real evil, cook up a crop killer instead, and watch everyone die of starvation.

Again, physics comes out on top of the nerd hierarchy mostly because it produces controllable status symbols, rather than horrifying, self-replicating monster events. What was that about power again?


Craig, Stephen: My comment @31 was not really intended to further the "OMG why would you do such a thing" discussion, though it appears to have done just that. It was more to say that I found the premise distracting, in that it failed to match the title and conclusion.

What it comes down to is whether the probing civilization cares about non-lethality vs. habitability vs. freakin' utopia, and I believe that continuum was sloppily addressed by the original post.


My own take on this, and ref my previous post @48 and various other comments– thought experiment more shows how completely vulnerable humans are without tech and social infrastructure. We haven’t even got fur. Me I’d drop a dog. If a dog survives for a few days we can probably make it habitable without a massive tech overhead.

Ref the next though experiment (Charlie@73), it gets really complicated if the biosphere needs any intervention from its human inhabitants to keep it working, because then you get into the how many people to keep a society afloat without a net knowledge loss every generation. Suddenly you need a very big biosphere.


The plural of beef is beeves.


Alex @87

Aye, it's grim up north.

On the other hand, even at this time of year it would have a reasonable chance of hitting a warm spell and not wandering over a cliff edge. But my point was more that we brainful inhabitants of the UK don't see "the wild" as very high up our list of threats (actually, I think this was Charlie's point). But things may be different in the US, where many families are only a generation or two from living memory of living in the wild and where you can still walk into lethal predators with such ease.


Charles, First let me say I've been lurking on this site for years, primarily to find out if you've written (and published) anything new since I already have everything else you've done. I've never felt inclined to post until today and this after reading your amusing Gedankenexperiment. Then I killed an hour reading all the response posts, plus the requisite detours to links the posters added, including reading Bliss' "meat" story twice on two different sites just because I liked it so much and hoped one might be better than the other. Unfortunately they were identical, like your hardcopy and pdf versions of "Accelerando".

All that said, I like where you're going with this. I have a pretty good idea from your previous writing that you're not going to take the easy way out and point to an as-yet uninvented miracle to solve every plot line problem, but would like to have as they say, plausible deniability concerning the science. Kudos. :)



But 'beef' is already the plural of cows, no ?


Corwin @18 and Craig @29:

I must be one of those soulless zombies, because to me, given the question "If you were stuck on a desert island with one other person, who would that person be?", the answer "One with a satellite phone with solar charger, and a solar distiller for water" is entirely natural, and in no way ironic/condescending. If I had not already read your exchange, it would never occur to me that the question's originator may consider it a smartass answer and/or offensive. This is JUST HOW MY MIND WORKS.

FWIW, Larry Niven is one of my three favorite SF writers, and I suspect his answer to "If you were stuck on a desert island..." question would be along the same lines. Creative ways of getting out of sticky situations is something at which Niven's characters excel.


@93: No, "beef" is a bastardized French cow. "Beouf".



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