I checked your link to the hydroponics guy, who says that a completely sterile environment would be perfect, but in practice you'll never get one.  The only reason why bacteria and fungus are necessary for a balanced system is that you need the more benign forms of bacteria and fungus in order to make it harder for the more destructive bacteria and fungi to establish themselves.  So, I have imagined a hypothetical environment in a space station where I can completely control my hydroponic environment and keep out all bacteria, which even your own referenced expert agrees would be perfect.  Can it ever happen?  Well, perhaps eventually.  I am not expecting it to happen in my lifetime.  I just like to speculate about possibilities.

And as far as the nitrogen-fixing bacteria, of course they are useful - but in a hydroponic system you can just add your own nitrogen, you don't really need bacteria.

Right now, obviously the human race still depends upon bacteria for many things.  And is vulnerable to bacteria.  And it is still a good idea to keep the salmonella out of the cookie dough.

And as far as the nitrogen-fixing bacteria, of course they are useful - but in a hydroponic system you can just add your own nitrogen, you don't really need bacteria

Nope. Molecular nitrogen is not what the plants need - it is compounds of nitrogen that are produced by the bacteria. Perhaps you'll respond that all you would have to do is add those compounds to your hydroponics vat, but where would you get them? I suppose you could synthesize them in a chemical factory, but it certainly would be easier to use bacteria that have evolved to do the job.

Yes, it is easier to use bacteria to synthesize these compounds.  However, we don't always choose to do things the easy way.  If I want to live in a bacteria-free environment on my space station, lots of difficult things have to be done to make this possible.

If you are going to sarcastically tell me that "machines never break down or turn on their users" I can be just as sarcastic.  That explains why we don't use any machines, they are much too dangerous.

In theory, instead of having to ride everywhere on horses, we could build some kind of self-moving or automotive machine, that would carry us even faster than horses, and with less resulting manure on the road.  But clearly we would never want to do that, because of the tremendous risk that these macines would get out of control and suffer high speed collisions in which people could be killed.  Right?

Medical nano-bots would bring with them both new risks and new opportunities.  We would probably try to figure out some way of managing the risk, rather than just abandoning the idea.  Also, technically nano-bots will be very hard to invent.  It's much easier to think up these ideas than it is to implement them.  But as a speculation about what the future may bring, it is not unreasonable.  I will add that the high-tech future of the nano-bot is not the most likely one as far as I can determine.  It is more likely that civilization as we know it will collapse before we advance to that kind of level.

Medical nano-bots would bring with them both new risks and new opportunities.  We would probably try to figure out some way of managing the risk, rather than just abandoning the idea.

You say that the immune system has risks and we should try nanobots, which you admit will have risks.  The human immune system has been fine tuned by millions of years of evolution.  What makes you think that human ingenuity will do better on any kind of realistic time frame?

In the book Where is God When it Hurts?, Philip Yancey talks about an attempt to build an artificial pain system for people who can't feel pain.  The researchers decided that they would do a better job than nature and create "pain" that doesn't hurt.  What they found is that pain doesn't work unless it is, well, painful.  Anything else will just be ignored.  The point is, the human body is the way it is because it works.  It doesn't work perfectly because sometimes you have to make tradeoffs, accepting some risks in return for results.

I'm not saying that it is impossible to improve on evolution/nature, but it is certainly not going to be easy.  And we may find that you simply can not eliminate risks without severely limiting the results.

You ask me what makes me think that human technology can do better than our own immune system, in any realistic time frame.  But I didn't state any time frame.  I merely said that it might eventually happen.  This is a science fictional speculation.  And human technology has a history of surpassing nature, at least in some respects.  Even such a simple thing as corrective lenses, allows us to see better for more years of our lives, than if we would if we depended solely upon the eyes that we are born with, eyes which, like the immune system, are the product of millions of years of evolution.  Evolution is great, but it isn't everything.

The fact is, a TREMENDOUS amount of human illness can be traced to failures of the immune system, which can be over-active and cause auto-immune disease, or insufficiently active and fail to get rid of some infection, or cancer cells.  We could in theory do far better with an artificial, programmable system, which could be told what it needs to do, when a person becomes ill due to an immune system problem.  And all of that is in addition to the most obvious use of an artificial immune system, which is to replace the immune system of a person who has an immuno-deficiency, such as a person with AIDS (although it is worth noting that there are many other possible causes of immuno-deficiency).

I do not doubt that this hypothetical technology would be extremely difficult to devise, and I certainly do not expect to live to see it, but it is a legitimate speculation.  There really is no way to know what kind of medical advances may eventually take place, since eventually is a long time, unless the human race becomes extinct, of course, and even then, an artificial immune system could still be invented someday by a race of highly evolved octopi, who will colonize the land and take over as the dominant organism on the planet Earth, long after the human race is gone.  Octopi paleontologists will marvel at the amazing ruins left behind by us, the lost race of humans.  They will marvel that we accomplished so much, and without even a single tentacle!  (I am not counting the tongue, although it is somewhat tentacular.)  

Programming an immune system is like programming in BASIC - all variables are global and there are no subroutines.  Too many variables all stomping on each other.   Even when such a thing is available, and I have no doubt that one day it will be, I'd stay far away from it, after all it might work as well as cars and computers.  Accidents will be fatal and viruses will have a whole new meaning.

I said from the beginning that it would be very difficult to create an artificial immune system, and of course, as you point out, immune systems have to deal with a lot of variables.  But this is somewhat like the larger problem of artificial intelligence.  Even though it may seem impossible to create true intelligence in a machine, we do have proof of principle; if the human brain is capable of intelligence, then it is possible in theory to design a machine that will artificially re-create what the human brain does, with whatever modifications or improvements seem appropriate.  Similarly, since the human body does have an immune system which, despite certain occasional failures or errors, does generally work, it would therefore be possible to build a machine which artificially re-creates the process that is already used by the immune system, but which does so with whatever modifications or improvements we may find necessary.

There do exist a number of machines which can perform the functions of organs of the human body; we have built artificial hearts, lungs, kidneys, and joints.  Artificial ears and eyes are coming along, but not perfected yet.  While all of these are tremendously simpler to build than such things as an artificial brain or immune system, I think that at this point we can safely predict that anything done by any biological system could, with enough research and development, be simulated by some kind of machine.  In the case of the immune system, the research and development would be an enormous project.  I do think that logically, it will be done eventually, provided that technological civilization survives.  There is no telling how long it will take.  Who knows, maybe a century, a millenium, a million years, a billion years.  Hard to say.

They may also marvel at the tastefulness of our erotica (NSFW)

erotica (nsfw)

woops

No, I agree, and am as much a technophile* as any.  It's all a question of whether it's worth it on balance: antibiotics have side effects, but that doesn't mean we shouldn't take them.  That said, it's dangerous to automatically assume that a technological/artificial approach is automatically better.

* It seems weird to me that Firefox's dictionary has "technophobic" and "technophobia" but not "technophile."

Q: What do you think of western civilization? Gandhi: I think it would be a good idea.

It may well be that using nano-bots rather than white blood cells will prove not be be an improvement.  But the human immune system is very troublesome.  It often over-reacts, causing allergies, and auto-immune diseases which are often extremely serious, and it also often fails to react sufficiently, thereby allowing people to be killed by infections or by cancer.  Now, the answer to these problems MAY simply lie in the learning how to fine-tune our own immune systems.  Maybe there is a way to make them work better.  But it is also possible that better results can be obtained by building an artificial immune system.  It is really too early to say where future medical research may lead.

How old do you think I am?   Not even my parents are old enough to have any recollection of the depression or the Nazis.  But yes, I do wonder if factory farming is to blame.  Because my parents were smart enough that if all of us had gotten the "flu bug" after eating something with raw egg, they would've figured out it had something to do with the food.  

In Japan, it's almost impossible to find a restaurant that does not serve a dish with raw or only partially cooked egg. I don't eat it, but everyone else seems to think it's the best thing ever...

And they'd be correct, dgraham! :D  Puts hair on your chest!

Most of the katsudon I've had in the US will have partially cooked egg as well. Usually not as runny as the ones I've had in Japan.

- derumi (del-me)
"It is the farewell kiss, you dog!" - Muntadhar al-Zaidi

We do our best to buy free range eggs and beef, exactly because of these issues.   Along with organic fruits and vegetables.  But I know I'm privileged because I can afford these things.  

I'm boggled that no one has studied whether the hormone & antibiotic cocktail fed to animals travels up the foodchain.  We've certainly noticed metals and other byproducts accumulating in larger predators.  But we carefully look away from these issues with respect to the things we eat.

With respect to raw milk, I'm not sure what to think.  My parents swear by it, and think homogenized milk is not good for you.  I worry a bit about contamination.  On the other hand, I was reading about breast milk when I had kids, and studies say that the antibodies in the breast milk kill bacteria (so you can safely leave it out for considerably longer than "normal" milk.)  I suspect the same may be true of raw milk from healthy cows.

Take two glasses of milk, one raw and one pasteurized, contaminate them both with e-coli.  Over time the helpful bacteria in the raw milk will disable the e-coli and the lack of bacteria in the pasteurized milk will breed the e-coli.

Eggs are fine on the counter for weeks, even in hot countries like Africa.  Meats can be dried as well as salted.  Chicken can be harvested the day you are planning to eat it.  Roots and squash can be stored in a root cellar or even just buried in a hole in the ground.   In the cold countries you can leave large sides of beef in an unheated room to freeze naturally.  Carrots and potatoes can be stored in the ground and harvested the day you want to eat them, even during the winter months.  Kale, chard, arugula, mustard greens and some other greens can be harvested year round even in cold and snowy areas.  Apples and kiwi can be stored in a root cellar for year round use.  Cheese can be safely stored in a root cellar for years at a time.  Cabbage can be fermented or pickled as can many other veggies.  Nuts can be harvested and dried over a wood stove and stay good most of the year.  Grains and rice can be dried and stored for years in a cool room.

Organic and local food does owe a debt of gratitude to industrial food - 'thanks for fucking up the system so bad as to drive people back to the basics'

None of that goes against anything I wrote. Potatoes, root vegetables, squash and grains are starchy, cheese is bacteria cured, and pickling involves salt preservation. As for the rest, unheated rooms, root cellars, chicken coops and winter harvesting aren't really viable options for city dwellers.

What gerry said, but also, don't forget that a lot of those crops were not widely available until just "recently".  Potatoes, maize, and a variety of other veggies were a purely South American thing until the 15th century.  Even in areas where the crop was "native", there could be a wide range of availability in any particular region, depending on if seed for the particular crop was available.  You couldn't just go to the store and buy seeds / seedlings.  All of that availability that we now have is due in large part to the mass distribution systems developed by, you guessed it, industrialized agriculture...

Ce n'est pas une pipe. C'est une signature.

In the 1500s in California the first nations tended a massive permaculture garden covering much of the state.  They pruned bushes, burned brush annually, tilled the soil, transplanted and sowed seeds.  There was a population density of 1 person to 2 acres.  They ate over 200 different varieties of foods.  Today we eat dozens of varieties of foods.  The availability of the past is disappearing due to industrialization.

The store was the entire outdoors, it is currently a little bare on the shelves because we haven't been managing it properly, but it wouldn't take much to get it back up to production.

Man, I ain't got time for no bakin'!  I need to stuff my face NOW!