• Log in with Facebook Log in with Twitter Log In with Google      Sign In    
  • Create Account
  LongeCity
              Advocacy & Research for Unlimited Lifespans


Adverts help to support the work of this non-profit organisation. To go ad-free join as a Member.


Photo
- - - - -

How do YOU see the concern with overpopulation handled?


  • Please log in to reply
25 replies to this topic

#1 TelepathicMerg

  • Guest
  • 67 posts
  • 4
  • Location:San Jose, CA

Posted 15 December 2010 - 05:50 PM


Assuming we have achieved immortality today, how do you see resolving the problem of overpopulation? Anyone?

#2 TelepathicMerg

  • Topic Starter
  • Guest
  • 67 posts
  • 4
  • Location:San Jose, CA

Posted 15 December 2010 - 05:52 PM

Personally, I do not see population as a problem in advanced societies but a benefit. However we are yet to realize it via improvement of knowledge and gaining of more wisdom..

#3 brokenportal

  • Life Member, Moderator
  • 7,046 posts
  • 589
  • Location:Stevens Point, WI

Posted 15 December 2010 - 07:15 PM

I see a main part of the solution being in helping to reduce the perception of over-population as an imminent uncontrollable catastrophe.

Hence topics like this: http://www.imminst.o...tion-challenge/

Like you say, there are also scenarios and times when we may/ probably will need expanding population too. If the world can handle 100 billion people, then thats a much greater percentage of people helping this cause, and people we can convert. Then also, if we make it out into space, which seems inevitable, then it seems there will be a time when maximum population increase is encouraged again.

sponsored ad

  • Advert

#4 Athanasios

  • Guest
  • 2,616 posts
  • 163
  • Location:Texas

Posted 15 December 2010 - 11:05 PM

If I were writing a science fiction book, I would have a window period of legal procreation. Mainly because it would be a fun idea to play around with. Every 200 years, there is a 10 year period in which anyone can have a child.

In reality, I don't think that it will be much of a problem. If we have the tech for immortality, we will have the tech for handling it. Similar to how Kurzweil saying that we plan for linear growth into the future, we tend to think of these ideas in isolation, instead of growth in other science and tech at the same time.

#5 Ben Abba

  • Guest
  • 24 posts
  • 0
  • Location:Summerlin, NV

Posted 16 December 2010 - 04:48 PM

Personally, I do not see population as a problem in advanced societies but a benefit. However we are yet to realize it via improvement of knowledge and gaining of more wisdom..


I totally agree with you; especially since it is a BIG UNIVERSE out there with plenty of room for more people than our current society is capable of producing.

#6 mikeinnaples

  • Guest
  • 1,907 posts
  • 296
  • Location:Florida

Posted 16 December 2010 - 05:17 PM

If we have achieved immortality there will need to be a temporary measure to remove overpopulation and consuming all of our planet's resources up until the point we figure out a way to expand beyond our planet. The temporary measures would most likely have to be disallowing general procreation. Accidents will happen and people will still die due to numerous reasons. A lottery should then be put into place for qualifying couples to be allowed to have a child to replace the life that was lost. Yes, this is extremely messed up, but it is the only way I can see us reliably controlling growth until the point in time where it no longer needs to be controlled. Again, it would be temporary.

#7 TelepathicMerg

  • Topic Starter
  • Guest
  • 67 posts
  • 4
  • Location:San Jose, CA

Posted 16 December 2010 - 05:31 PM

If we have achieved immortality there will need to be a temporary measure to remove overpopulation and consuming all of our planet's resources up until the point we figure out a way to expand beyond our planet. The temporary measures would most likely have to be disallowing general procreation. Accidents will happen and people will still die due to numerous reasons. A lottery should then be put into place for qualifying couples to be allowed to have a child to replace the life that was lost. Yes, this is extremely messed up, but it is the only way I can see us reliably controlling growth until the point in time where it no longer needs to be controlled. Again, it would be temporary.


But the term "immortality" indicates impossibility to end life, does it not? Why would then be a problem with resources or scarcity? Would any imposition of any rules be possible? What would life without fear bring to a society and its member?

#8 mikeinnaples

  • Guest
  • 1,907 posts
  • 296
  • Location:Florida

Posted 16 December 2010 - 06:08 PM

But the term "immortality" indicates impossibility to end life, does it not?


Not really. My assumption if that the first step of immortality will be through indefinate life extension. This leaves room for death through other means ...accidents, murder, etc. We can argue that at some point we will exist outside of our human bodies, but I am firmly under the belief that we would no longer be human at that point or even technically alive.

#9 TelepathicMerg

  • Topic Starter
  • Guest
  • 67 posts
  • 4
  • Location:San Jose, CA

Posted 16 December 2010 - 06:52 PM

But the term "immortality" indicates impossibility to end life, does it not?


Not really. My assumption if that the first step of immortality will be through indefinate life extension. This leaves room for death through other means ...accidents, murder, etc. We can argue that at some point we will exist outside of our human bodies, but I am firmly under the belief that we would no longer be human at that point or even technically alive.


Perhaps not exactly "outside" but with a different ratio of physical to informational, indicating a small but a highly advanced creature (:....


I actually can imagine a state of nearly total security where the survival of the physical state could be 99.9% assured. This would be a condition where the physical body would be hidden while its owner would be functioning in the world (virtual or not) as a projection.


I also can imagine as achievable a state, where the body undergoes metamorphosis in case of injury... I even can imagine a discovery of life forms which are continuation of our identities beyond "death"... I can imagine a conversation with those via some type of projecting... My preference (not always (:) is to think of singularity with its solution(s) beyond our current imagination...

Anyway, it is still an interesting question: How would we change in a state of no fear for physical survival?

#10 niner

  • Guest
  • 16,276 posts
  • 1,999
  • Location:Philadelphia

Posted 16 December 2010 - 09:03 PM

But the term "immortality" indicates impossibility to end life, does it not?

Not really. My assumption if that the first step of immortality will be through indefinate life extension. This leaves room for death through other means ...accidents, murder, etc. We can argue that at some point we will exist outside of our human bodies, but I am firmly under the belief that we would no longer be human at that point or even technically alive.

Right. Unfortunately, we have elected to redefine the word 'immortality' to mean indefinite life extension; i.e. the absence of (or continual repair of) aging. This leads to much confusion as the rest of the world uses a different definition. I suppose at some point in the perhaps distant future, we will be sufficiently post-human to consider ourselves no longer human. At present, the use of various artificial body parts, medication, and other treatments doesn't seem to make people non-human. Eventually, if we exist on a computational substrate, I guess we would no longer be 'alive', assuming we define that as a carbon-based life form or whatever, but we would still have consciousness, which is the important thing.

#11 BrandonKing

  • Guest
  • 34 posts
  • 22
  • Location:Merced, CA

Posted 14 February 2011 - 09:44 AM

i see the answer lying in Space Travel and Colonization of other planets and if the Universe is infinitely growing as suspected by many people, myself included, then no matter how large we grow as long as we can either find inhabitable planets or terraform uninhabitable planets we can theoretically grow forever without having to theoretically worry about overpopulation

though i am still 100% convinced if religion never existed we would probably be exploring the galaxy in person by 1:44am Monday February 14, 2011 because science cannot co-exist with religion without one being persecuted as shown during the 1000 years the Catholic church ruled the known world a time known as the Dark Ages in which very little scientific achievements were made during that entire 1000 years and barely 400 years later we are now in the modern age just think what an extra 1000-2000 years would have let us achieve

#12 distinct

  • Guest
  • 114 posts
  • 45
  • Location:Glastonbury, CT, USA

Posted 14 February 2011 - 01:31 PM

I'm sure it will handle itself, not very nicely either.

#13 BrandonKing

  • Guest
  • 34 posts
  • 22
  • Location:Merced, CA

Posted 20 March 2011 - 05:46 PM

What no one seems to remember is that we can always build up we dont gotta continue building out as most arguments are based upon

not too mention the threat of overpopulation will spur a colonization race of the habitable planets/planets that MAY be habitable and as technology increases we will be able to expand farther and farther into space and a commonly held theory is that the Universe is infinite so theoretically we can expand infinitely into space if thats the case and so given the correct advancement of technology we may NEVER have to worry about total overpopulation!

#14 Guest

  • Guest
  • 320 posts
  • 214

Posted 02 April 2011 - 12:43 AM

We had some extensive discussions about that topic at the SENS Foundation forum and the at the old Methuselah Foundation forum. To put it bluntly, given what we know about physics and not considering forceful minduploading there is no way other to introduce strict birth controls. The reasoning was roughly as follows:


If we eleminate aging related diseases and other common causes of death (especially infectious diseases in the 3rd world) every birth rate that is significantly above 1 child per women is non-sustainable. This is statistically speaking and for her whole life which can last 1000nds of years.

I read that people are optimistic about space travel, but without realising that this is in no way a solution to overpopulation. I mean we are talking about the extended future, 1000s of years and more. Even with small birth rates such as 1,5 or 2 childs per women during her first 300 years our solar system would run out of space and habitable places very quickly - even considering "small tasks" such as transforming Jupiter into a 100 G paradise for humanity.

Intra galactic space travel on the other hand is not very viable as even with advanced not yet build drives it would take decades to get just to our closest neighbouring stars. Relativity is a simple fact. Even if we extend our current knowledge of physics those new theories will not invalidate relativity, the same way that relativity did not invalidate Newton - but includes it as a special case for small velocities. This means that for non-zero mass objectes Einstein will remain god unless you miracously define away basic causality and invent arbitrary time travel. No matter whats your new more comprehensive theory - it has to include the empiricially validated theories of relativity at least as a special case.

This means that there is a fixed limit - c - of speed for us. And the closer you get to that speed, the more energy you need. So you either travel to other stars with not much more than 0,1 c or you need incredible amounts of energy (exponentially growing for every little step you get closer to c). That way our stay-home population is exploding faster than we reasonably can explore and ship people to alternative places, say 100-200 ly i.e. ca. 1000 travel years, away from our solar system. Exploring places which are not in our immediate region of the milky way could easily take 100.000nds of years. Travel to other galaxies except to our nearest partners would take many millions and billions of years.


There are just two options to deal with limitless population growth in our physical world: high death rates countering high birth rates, and high birth rates is everything signficantly larger than 1 child per women during her whole life. Or in case of very low if not zero death rate a low birth rate of not much more than 1 child per women. If we want near zero death rates we have to think about methods to limit birth rates here on earth. It is of course legitimate to discuss various measures such as forceful sterilisation and a strict ban on treatments to restore fertility. But wishful thinking about non-physical space travel does not help. This not meant to be offensive, but you need to get your arguments straight if you intend to advocate life extension.

#15 Elus

  • Guest
  • 793 posts
  • 723
  • Location:Interdimensional Space

Posted 02 April 2011 - 03:05 AM

The overpopulation argument vs. immortality is invalid. Gavrilov et al have addressed the concern using mathematical models which use current trends and technologies. Paper here: http://longevity-sci...ons-RR-2010.pdf

Furthermore, it is rather shortsighted to believe we will stick to our current bodies and their archaic metabolic energy requirements and abilities. Population won't be any issue given the fact that we'll be able to enter worlds of our own design and perhaps live there permanently with the advent of AI, virtual worlds, and the like.

#16 niner

  • Guest
  • 16,276 posts
  • 1,999
  • Location:Philadelphia

Posted 02 April 2011 - 03:34 AM

We are seeing population declines across the developed world. It seems that when people are educated and empowered, and children have a high likelihood of survival, that people naturally prefer fewer children, as in less than the replacement ratio. We will need to adapt our economic systems to cope with falling, or at least stable populations, rather than relying on unsustainable increases. It would be entirely possible for the population of Earth to decline significantly before we get anti-aging medicine rolled out to as many people on the planet who are interested in using it.

As Elus alludes above, there are other options besides "colonizing the universe", which IMHO is not in the cards. Look at the plummeting feature sizes of microprocessors: At some point in the not too distant future, a computational substrate with molecular feature sizes will have the capacity to "run a human consciousness". We could get small. We could get really small. I consider a dramatic reduction in our resource requirements to be far more likely than interstellar travel or planet-scale engineering projects, barring some rather dramatic new physics.

#17 robomoon

  • Guest
  • 209 posts
  • 18

Posted 02 April 2011 - 02:01 PM

Someone should try telling this to my father. Despite of the usual corporal performance issues from aging, it would be quite a hard time for my father to tolerate a dramatic reduction in his resource requirements. I would not tell the details in terms of his corporal performance issues because I respect his privacy. But you know, our elderly got some of the usual corporal performance issues like gall stones, diabetes, heart attack, prostate cancer, teeth/gums decay/decline, more-than-occasional forgetfulness, reduced immunity, etc. Yet, why would they be happy to give up driving their big cars, owning secondary residences near their so much younger lovers, spending some time on sailing yachts, playing golf in Dubai, etc., when they became used to it for quite a while?

Overpopulation is not only about the number of humans. There are some people around who are more aware about a resource distribution problem but overpopulation. So I'm inclined to feel that the problem has something to do with consumption rates even when birth/death rates are no issue. Regarding the creation of computational substrates, there is an increase in the overall size. All the computer stuff together makes a very large pile. The number of computers is still growing and the number of humans too. They require more space, energy, and further natural resources in this setting.

Right, physical space colonization should expand according to economic rules. It is feasible to send robot machinery to the moon long before an investment into something else but traditional rocket systems must be deemed necessary. So please do not bother about cheap space elevators, solar satellites for the whole world, terraforming of Mars with a nuclear bomb, and whatever silly fantasy some people got. The moon is not too far an environment that can be industrialized to supply people with what they are craving: a fully automatized production of nanosized electronic parts for processors and flash drives.

An experiment causing gray goo on our planet should be avoided at all costs to secure the very life on it. On the moon, however, nobody would be harmed if an experiment goes fail, turning all biological bodies into a fungus-like goo. Some bacteria would die in a lab over there, who cares? Since the transportation of a system for self replication in nanotech style requires no great number of rockets for transportation, the moon is important in this planning. And I bet, its the best. If experiments for the sake of nanotech go fail, much security can be expected from the distance between the moon and human beings.

Thus, automated space colonization and the creation of computational substrates belong together.

Edited by robomoon, 02 April 2011 - 02:04 PM.


#18 Guest

  • Guest
  • 320 posts
  • 214

Posted 02 April 2011 - 06:29 PM

Just to clarify, I don't say that overpopulation will happen unavoidably if we don't interfere. It just might be the case that people decide not to have kids at all on average - in this case: problem solved.

But the notion that population declines are projected in non-life extension scenarios or short term calculations as done by Gavrilov are not really applicable if we talk about the long run consequences of near zero death rates. Imagine people live more than 2000 years or possibly 10 of 1000s of years. Even one child per 1000 years per women will be unsustainable and space colonization is not a viable alternative. Maybe people will freely choose to get a kind of minduploading or "virtual" kids rather than real ones etc. But there might as well be parts of the population who stick to traditional patterns and might it just be out of religious motivations.

Look, I don't want to start a discussion about "Religion will immediatly vanish ones LE has arrived you fool!" or "Everyone will do minduploading which will be availbale in 15 years and no one will be so stupid not to do it!". As a matter of fact population explosion can happen rather quickly if LE should be here and people do not immediatly change their attitutes towards having (real) kids. Just handwaving it away with fictious concepts such as FTL drives etc. is not a good strategy in a public discussion.

#19 robomoon

  • Guest
  • 209 posts
  • 18

Posted 02 April 2011 - 09:49 PM

OK, after reading this now, it looks strange to myself calling it automated space colonization instead of automated space utilization. Not after this alone, but also after myself taking a look at the next two responses by readers of the Lifeboat blog message The Existential Importance of Life Extension here http://lifeboat.com/...ension#comments that appeared after mine.

#20 niner

  • Guest
  • 16,276 posts
  • 1,999
  • Location:Philadelphia

Posted 03 April 2011 - 05:43 AM

I really didn't explain myself well at all, so let me try it again. When I was talking about reducing our resource consumption, I wasn't talking about trading in the Escalade for a Yaris. I was talking about a far-future transhuman concept where our consciousness inhabits a microscopic computational device. Robomoon and I weren't just not on the same page, we weren't even on the same planet... I'm just looking at what known physics says that we can and can't do. I think that we are going to have an extremely wide sphere of transhuman possibilities long before we discover the physics (if we ever do) that would make interstellar travel reasonable. Mind you, these kinds of ideas are not intended for arguing with the average person on the street. People should be comfortable with (extreme) transhumanism before you tell them it will be cool if no one ever dies because we'll just shrink ourselves down to microscopic size, and carry super powerful sidearms to dispatch ravenous dust mites...

Also, consider that some time in the next century, 99% of the human race, if not 99.9% might die. There are all manner of ways such a thing could happen, so that would reset the "population bomb" by quite a few years, assuming the survivors didn't lose too much of our technology. There is just so much that is unknown here. What if we cure physical disease and aging, but we don't get depression sorted out, so people on average only live a couple hundred years before they kill themselves?

I'm dancing on the bizarre fringe here, but really I think the answer to the "overpopulation" question is pretty prosaic. By the time aging is no longer an issue, the population will already have shrunk substantially. People will still die due to accident, choice, or disease that still crops up occasionally. Birth rates among people who are extraordinarily old will probably be very low, and by the time overpopulation could actually become a problem, we will have technology so advanced that it's pointless to even speculate what it will be like. If it came down to it, we could make anti-aging treatment be contingent on sterilization, though I doubt that we would ever need to be that draconian.

#21 robomoon

  • Guest
  • 209 posts
  • 18

Posted 03 April 2011 - 06:01 PM

99% of the human race, if not 99.9% might die some time in the next century. So if the human race has 10 Billion people at one time in this century and 99% dies in the next century, only 1% are just 100 Million survivors. Wonder if the fatal source can be a new kind of airborne virus or prions and what survival ability those 1% would have in common. Probably a blood type leaving them immune against something which could be a HIV/flu hybrid or some previously undetected prion creation.

The chance for a complete protection against one fast spreading infection mentioned above is not very high, since a virus or prions wiping out 99% of the human race in one Century would probably overcome any natural immunity due to mutations. Therefore, there will be the great threat of human extinction. What do you think will offer protection against a fast spreading pathogen? Think, against an airborne pathogen, security will come from a lower population density. The further afar you are from the others who got infected, the more secure you are.

Probably 10 Billion humans might fit into a country like Germany, but a higher population density will make an airborne contaminant spreading more quickly. The risk is only getting lower when population density decreases. Thus, a higher population density is a risky argument against the subject of overpopulation. Higher population density in only one area contains the prospect of rather fatal consequences for the human race. Anyways, people are bearing an unnecessary risk while putting all their eggs in one basket which means all of men in only one area as large as Germany.

The lucky thing in the unlucky event is that a lower population density from a decreasing population will slow down contamination. Still, the actual situation is that the number of improperly controlled existential risks is increasing with scientific research in areas like particle acceleration. There is much more that endangers men but only some insufficiently controlled experiments in biology laboratories causing the creation of a highly fatal virus. Since great breakthroughs in physics are required to get to the point where microscopic computational devices are gaining consciousness like humans, an overall acceptance of some scientific research is practically a reason for announcements about an increasing threat condition.

The world has to be aware about its fate no matter if some current indicators like the GETAS Threat Level http://lifeboat.com/ex/getas have been assigned the same or not. Give the problem a different name but Overpopulation to get a different term for the solution: Automated Space Utilization!

Edited by robomoon, 03 April 2011 - 06:17 PM.


#22 Guest

  • Guest
  • 320 posts
  • 214

Posted 03 April 2011 - 07:43 PM

So you are saying that we don't have to deal with overpopulation concerns because luckily a supervirus could kill virtually all humans except a couple of guys in the forseeable future? Without wanting to further elaborate the valditiy of that statement: please do not try that as an argument in a discussion about life extension with the average Joe or any media guy ...

#23 chris w

  • Guest
  • 740 posts
  • 261
  • Location:Cracow, Poland

Posted 03 April 2011 - 11:58 PM

Also, consider that some time in the next century, 99% of the human race, if not 99.9% might die. There are all manner of ways such a thing could happen, so that would reset the "population bomb" by quite a few years, assuming the survivors didn't lose too much of our technology.


I have to say you caught my attention. What magnitude of possibility do you think this has ? What causes are you thinking of here ?

Ya know, I hear about that Apofis asteroid being scheduled for proximity in 2030's but I choose to believe sir God will spare us, and if not - we will be able to fly there with something like the Don Quijote and Sancho Pansa probes (gotta appreciate the humor), to deflect the course, or you know, just send and leave there Bruce Willis with a detonator :cool: ?

Seriously, what makes you think so ?

Edited by chris w, 04 April 2011 - 12:02 AM.


#24 brokenportal

  • Life Member, Moderator
  • 7,046 posts
  • 589
  • Location:Stevens Point, WI

Posted 04 April 2011 - 12:07 AM

The concept of over population is such a non issue in the context of the goal we are talking about, unlimited lifespans, that it is readily defeatable by numerous arguments. You can find them all around the forum. One of my favorites, that has silenced over population touters nearly every time I use it, again, is this "Under-Population Challenge" topic here.

The important thing to remember is that it is not something that needs to make anybody say,

"Oh, hey, wait a minute, I think we better hold up on that support for unlimited lifespans because of this over population deal."

There is no room to think that at all. There is only room to go all in on support for unlimited lifespans, turn up the gauges and then double down from there.

#25 niner

  • Guest
  • 16,276 posts
  • 1,999
  • Location:Philadelphia

Posted 04 April 2011 - 02:24 AM

Also, consider that some time in the next century, 99% of the human race, if not 99.9% might die. There are all manner of ways such a thing could happen, so that would reset the "population bomb" by quite a few years, assuming the survivors didn't lose too much of our technology.

I have to say you caught my attention. What magnitude of possibility do you think this has ? What causes are you thinking of here ?

Ya know, I hear about that Apofis asteroid being scheduled for proximity in 2030's but I choose to believe sir God will spare us, and if not - we will be able to fly there with something like the Don Quijote and Sancho Pansa probes (gotta appreciate the humor), to deflect the course, or you know, just send and leave there Bruce Willis with a detonator :cool: ?

Seriously, what makes you think so ?

We've had extinction events in the past; asteroid hits, supervolcanoes and the like. Another physical cause might be a gamma ray burst. These are very low probability events. I would rank a biological occurrence much higher. Humans are living in close proximity and traveling between all points. This has never happened in our history, and it creates a situation tailor-made for a really nasty infection. No one knew that AIDS existed until people started dropping dead. That was a virus that while highly lethal, is actually pretty hard to spread. Imagine if AIDS spread like a very contagious cold or flu, but there was little or no evidence of infection for a couple of years. By the time we figured out what was going on, most of us would be doomed. While the probability of a natural infection is a lot higher than an asteroid, my greatest concern is for man-made disasters. An engineered virus is an obvious possibility. As each year goes by and climate change seems to be happening faster than we thought it would, while at the same time the US Republican party holds as an article of faith that climate change is "a hoax", I'm beginning to worry about the possibility that global warming might be a lot worse than anyone expected. It wouldn't take that much change in climate and sea level to create massive displacement of people, economic disruption, and general chaos that might lead to something like a nation-state choosing to develop a biological weapon that turns out to be "too good". We shouldn't forget that we still have enough nuclear weapons to create a really large dent in the human population. That would be another temptation in a moderately bad climate change scenario. Then there's the end-of-life-on-earth scenario: We already know that our climate is littered with feedback loops and is a metastable system. What if we've underestimated the strength of a feedback condition, or there's a really important one that we missed? What if instead of a 5C average temperature increase, it's 50C? Or 250C? I think the odds of that are probably pretty low. Our knowledge of climate isn't perfect, but we are running the experiment anyway.

And then there's the Fermi Paradox. I think there are some very good arguments against it, but it's still there.
  • like x 1

#26 robomoon

  • Guest
  • 209 posts
  • 18

Posted 07 April 2011 - 01:08 PM

Good response about viruses. You can guess I know little about their functions and genetics, but I see there are people around here who have learned much more. However, here is something about a comparatively easier to understand agent that may not be dangerous like a virus, but good for starters: The Anthrax Terror http://www.airpower....win00/davis.htm published by the Aerospace Power Journal, 2000.

For something more advanced, http://www.sunshine-...intro/gebw.html states: Through genetic engineering, bacteria can not only be made resistant to antibiotics or vaccines, they can also be made even more toxic, harder to detect, or more stable in the environment.

The above online resources are not only talking about the military in the US, Russia, UK, Germany, China, and Israel. There are also sponsors of international terrorism. They include Iran, Iraq, Syria, Libya, Cuba, Sudan, and North Korea. So there is no need to worry about underpopulation. Even the less developed countries are equipped to spread their interests further, driving the masses of immigrants wherever they can escape through.

Edited by robomoon, 07 April 2011 - 01:11 PM.





0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users