In modern day society, few or many people have been fascinated with integrating robotic parts to their bodies. But sometimes that idea is taken to the next step, in which people want to have their entire bodies become robotic in nature.

So let’s say that humanity is capable of doing that. Normal people would have robotic brains, limbs, and other parts, and are somewhat connected to the internet. However, humanity isn't advanced enough to make limitless energy (essentially where we stand in energy production terms).

What are a few problems or disadvantages that would arise from humans turning themselves into robots?

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    $\begingroup$ This also might be unnecessary, but the people will still retain their personality’s. $\endgroup$
    – RotNDecay
    Mar 1, 2020 at 23:55
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    $\begingroup$ Doctor Who has been fighting those dudes since 1963. $\endgroup$
    – user535733
    Mar 2, 2020 at 0:15
  • $\begingroup$ 'make themselves robots' or 'make themselves into robots'? $\endgroup$ Mar 2, 2020 at 0:36
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    $\begingroup$ You can't reproduce, though you might be immortal (in case of death, your robot brain is backed up so you can be revived), but lots of your emotions will lose. I know that, it is one of my lifetime project. $\endgroup$
    – Shiz
    Mar 3, 2020 at 1:54
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    $\begingroup$ @RotNDecay: Good, so no Cybermen. $\endgroup$
    – Vikki
    Mar 4, 2020 at 1:28

14 Answers 14


Currently, robots do not last as long as humans.

Even old, restored cars tend not to last as long as humans, and still be functional.

And human bodies do not tend to become obsolete the way modern technology does. A new body every two or three years? Think of the costs, if an iPhone is around $1,000.

And, of course, there is always the security, the security upgrades, and the hacking. We get upset when our identity is stolen, so our entire bodies?

Imagine the business Norton would do. It puts an entirely different twist on 'Anti-virus software'.

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    $\begingroup$ YES! That's not even thinking of Solar Flare's, EMP bombs wiping millions of Digital Citizens while the flesh and bone remain unaffected......mmhmm..nice story there. $\endgroup$
    – Gustavo
    Mar 2, 2020 at 9:38
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    $\begingroup$ "And human bodies do not tend to become obsolete the way modern technology does." – Well, keep in mind that old hardware is often still usable. There undoubtedly a lot of pieces of computing hardware built in the 1960s and 1970s that are still in use, because they're just as useful now as they were back then. I got my current cell phone in 2016 and I have no plans to replace it; there's no reason why people would need to replace their entire robotic bodies every two or three years. $\endgroup$ Mar 2, 2020 at 12:43
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    $\begingroup$ @TannerSwett except if planned obsolescence were a thing for robotic bodies. It would be a nice twist! $\endgroup$ Mar 2, 2020 at 13:19
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    $\begingroup$ @Tanner Swett What about your car? How many cars have you gone though? The reason electronics from the 60's is still working is because it was not miniaturized to the extent it is today. At the micron level of today's IC's, the pathways are so narrow (a few atoms wide) that the atoms migrate into complete disarray within a few decades. No iPhone built today will be reliably functional in twenty years. The chips will be just a mess of atoms. $\endgroup$ Mar 2, 2020 at 13:39
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    $\begingroup$ There are plenty of old cars (100+ years) that still run just fine and we can build replica parts to keep them going indefinitely. Old computer cases can be 'modernized' by putting new motherboards, hard drives, etc. in them. The old software can be ported to the new hardware even if we have to use an emulator. With electronic minds we can back up our state every night or even every minute such that we would only lose a short amount of time - think of a person in a coma or with amnesia. There is no need for a new body if the old one still suits you. $\endgroup$ Mar 2, 2020 at 17:57

The term here isn't robots, it's cyborgs. This is also the premise of Ghost in the Shell.

The maintenance and security problems will be an expensive problem in contrast to an organic body that is semi-self repairing and sort of secure. Organic brains or memories can be manipulated(see con artists, infrasonic as a source of ghost sightings, or the work of Elizabeth Loftus), but they cannot be outright controlled or deleted in the same way cyberized brains can be.

You've also created some very interesting philosophical questions as an inevitable result of this technological advancement. What does it actually mean to be human when every part of a human can be replaced? It's a similar problem to the Ship of Thesseus. If no component of "you" is the original organic parts, are you still you?

It is also likely possible that this technology allows one to replicate your brain, because if brains can be entirely digital, they can be easily duplicated. Ghost in the Shell uses the concept of the Ghost as a result, the idea that there is something innately human, which is really just another word for a soul. You'd have to answer the philisophical question as to whether a soul exists.

  • $\begingroup$ I think the idea that mechanical brain can be easily duplicated is a bit naive. Complex IT systems are often really hard to duplicate - the state of the system is not just the stored data but also all intermediates and processes in progress. It's plausible to think that a brain-computer will also have many of these just as a biological brain making a copy an imperfect one. $\endgroup$ Mar 2, 2020 at 11:52
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    $\begingroup$ I think the worst problem of all is "copyright": How do you enforce no one creating another you? $\endgroup$ Mar 2, 2020 at 13:41
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    $\begingroup$ "If no component of "you" is the original organic parts, are you still you?" - If you think the answer is no, wait till you find out that the vast majority of your body gets replaced on a regular basis as cells die and get replaced. $\endgroup$
    – James
    Mar 3, 2020 at 1:57
  • $\begingroup$ The Ship of Theseus problem is not a problem at all. We already replace most of our atoms every few months, and hardly ever think about it. We have gotten used to the idea of having abstract possessions, so that I don't worry about whether the dollar I get from the bank is the same dollar I put in. The problem comes when the new tech violates the persistence of personal identity, e.g. mind grafts. $\endgroup$
    – Beta
    Mar 3, 2020 at 15:06

OK. So. Here's the assumptions I'm making with this answer:

  1. Humanity has figured out how to transfer their minds into robot minds
  2. These (base) robot bodies are on par with human bodies, in terms of dexterity, strength, etc.
  3. Parts can be replaced and repaired. All of them. If we can upload to one brain, we can transfer that brain to another brain, etc.

The biggest problem that I forsee is population. That is, once your population is made out of robots, it no longer expands. It can only shrink. Regardless of how tough the robot body is, things happen and bodies are broken. Occasionally, that will be the "Mind" portion. But, as there's no biological humans left, you can't have babies and can't add to the human population.

Now, you can add to the population with AI, but AI by definition aren't going to be humans. Your population of humans will dwindle, getting smaller and smaller. Similarly, as mentioned in @Adam Reynolds' answer, you might be able to replicate human "digital" brains, but... Are they human?

There's also the issue of religion. Many religions have the concept of a soul - Is the person's soul linked to their body? Do they "Die" when their brain is uploaded, or by uploading are they foregoing the potential afterlife? Do AIs, or copied human brains, have souls, and how does the religions treat them? Religion is a huge can of worms for a society that is in the process of uploading, but I'd imagine if everyone has already uploaded then that problem has largely been "solved" or isn't really thought about by people anymore.

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    $\begingroup$ You can also add to the population by copying. Just transfer your mind to a new brain without deleting the old one. (I've always been a bit unsure about the social consequences of that - do you end up with everyone being a copy of the same person? Are all those copies happy?) $\endgroup$
    – N. Virgo
    Mar 2, 2020 at 9:08
  • $\begingroup$ An interesting notion. Once we have the capability to copy (or transfer) the mind/brain to electronics a new one can be 'programmed'. We know there is a hardware versus software aspect to our 'selves' (nature versus nurture), so if we remove nature by creating the same set of brains we will still have variability in personalities. If we also understand the difference in the 'nature' aspect then we can also build hardware with subtle differences that will also alter personalities. It's an interesting rabbit hole to fall into... $\endgroup$ Mar 2, 2020 at 17:51
  • $\begingroup$ Religion is plastic. The theologians will adapt to the new technology somehow or other, the way they adapted to e.g. heart transplants. $\endgroup$
    – Beta
    Mar 3, 2020 at 15:26
  • $\begingroup$ Anti-upload religions or dogma will die out rather fast because their followers will be mortal and their "opposition" will be immortal beings. If they survive at all, anti-upload people will only be found in small cults or isolated religious groups similar to today's Amish. $\endgroup$
    – Dragongeek
    Mar 3, 2020 at 22:39


If you can upload yourself into one robot body, why not 1000? Travel the world...simultaneously! Of course, you need to buy all the bodies, but if each one can earn money on its own, then what's to stop your personal collective from growing without bound, until you can populate an entire new planet...all by yourself?


At first, humans will want to upload into humanoid bodies. But why stop there? Some freak will want to inhabit a robotic spider body. And another will want to be a huge cyborg elephant monstrosity. And yet another will want to become a commercial robotic bakery oven. Eventually, all the robots in society may, in fact, be humans (or former humans, depending on how you look at it). At that point, what exactly does it mean to be a human? Or does it?

Space Exploration

Obviously, travelling in space is much easier if you don't need the extensive life support systems that humans require. So robotic bodies would vastly simplify space exploration. Perhaps the ships themselves will be uploaded humans, as individuals or even families/collectives. The worst outcome of all is not getting shot out an airlock (which wouldn't exist on a ship without useless air in the cabin). The worst outcome is getting detached from the ship and floating aimlessly until your power supply ran out. And if the robots have a very long-lasting supply (micro-fusion or whatnot), then that could be a very long time indeed. On the plus side, they could have a "stasis" mode which lets them shut down until someone comes and rescues them. They could float in space for thousands of years, only to be accidentally discovered, repaired, and revived, little the worse for wear (cosmic rays will take their toll, but with adequately robust neural networks, will only result in memory degradation, rather than absolute mental loss).


Lots of folks said that the robot humans would stop advancing. I think this is an unnecessarily and wetware-chauvinist point of view. But the way in which I think an appearance of this might occur is that some humans might want to upload into a robot body that happens to be a structure. A building. Yes, some freak will want to become a building. Others will follow. And without locomotion, they will be limited to whatever the building inhabitants do. They could still communicate on networks, presumably. But they would be the equivalent of conscious plants. They might devolve into extensive navel-gazing, and slowly lose all motivation to advance. Or, they could use the free time to explore the limits of science and art and become the best mathematicians and musicians in the galaxy.



Just imagine the ultra wealthy never dying, just keep accumulating the wealth of society by preying on those weaker than them. People like Putin, who made himself "president for life" and others like him never dying.

In a society like that, change would be almost impossible. Death is ultimate reason to give someone else a chance.

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    $\begingroup$ Damn Meths, comin’ over here with their 969 years and shedloads of money tied up in complex interest. $\endgroup$
    – Joe Bloggs
    Mar 2, 2020 at 10:37
  • $\begingroup$ Progress and technology always trickle down to the population and things that only the ultra wealthy could afford a century ago can now be bought by homeless people. If digital immortality becomes commonplace, it will eventually be for everyone. Death doesn't give life meaning and isn't necessary for progress. $\endgroup$
    – Dragongeek
    Mar 3, 2020 at 22:43

We are the Cybermen

One of the primary villains in Doctor Who, the Cybermen are pretty much exactly what you are describing. They are described as normal run-of-the-mill people from the planet Telos. Originally completely organic, they gradually replaced various limbs and organs with robotic parts, reasoning that they were more efficient. Eventually, they went all the way, replacing their brains and thus transitioning from cyborgs to the "human mind controlling a robot" that you appear to be looking for.

Unfortunately for them, these changes caused them societal problems. The 11th Doctor aims out up pretty nicely, when he tells John Lumic (their creator),

Everything you've invented, you did to fight your sickness. And that's brilliant. That is so human. But once you get rid of sickness and mortality, then what's there to strive for, eh? The Cybermen won't advance, you'll just stop! You'll stay like this forever. A metal Earth with metal men and metal thoughts, lacking the one thing that makes this planet so alive: people! Ordinary, stupid, brilliant people!

This apathy, combined with their inability to reproduce, was their downfall; over time they gradually withered away, ultimately dying out due to attrition.

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    $\begingroup$ Stagnation after mortality is conquered can make for a nice theme to a story but I'm not sure how realistic it is. Let's assume there is sickness and death suddenly disappear. Would Newton still not have done anything for science? Ada Lovelace? Charles Babbage? What about a whole corporation like Microsoft or Apple, would they also stop producing new things? Would the thousands who post on StackOverflow (which is quite far removed for fighting for mortality) also stop doing that and stop trying to advance? I'm pretty sure we can and will grow in other directions. $\endgroup$
    – VLAZ
    Mar 2, 2020 at 8:49
  • $\begingroup$ You forget the dr who cyberman have an emotion turner-offer. Making them as soulless as any government. $\endgroup$
    – Dr_Bunsen
    Mar 2, 2020 at 13:13
  • $\begingroup$ @VLAZ I personally was not trying to express an opinion on the subject; I was merely stating that the OP's robot-men already exist in the realm of Sci-Fi, and giving specifics about why they fail. That being said, I do believe that that is what would happen. Eventually, everybody would be like Wowbagger the Infinitely Prolonged from the Hitchiker's Guide to the Galaxy series; everybody does everything, and then become immensely bored. Some, like Wowbagger, would find a dumb occupation (Wowbagger tries to insult everybody in the universe); nevertheless, society would stagnate. $\endgroup$ Mar 2, 2020 at 14:07
  • $\begingroup$ @Dr_Bunsen Not in the original series; there, the Cybermen were emotionless because of robotic brains. Regardless, both Old Who and New Who Cybermen have the same problem, which is why I was able to use a New Who quote. $\endgroup$ Mar 2, 2020 at 14:09
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    $\begingroup$ @Dr_Bunsen in the original series the Cybermen had robotic brains that were programmed with a digitized copy of somebody. These brains were incapable of replicating emotion. $\endgroup$ Mar 2, 2020 at 16:17

The fully robotic humans would die out, many of the cyborgs would already die out. They would eventually solve this but be more robotic intelligence than human intelligence in a robotic body.

The problem is that your body provides a lot of incentives. The incentive for gathering food, incentives to protect against damage, incentives to procreate and incentives to keep breathing to live. If you start replacing bodyparts all that is left is intelligence, but like a computer it does not have a will to perform tasks to keep itself "alive". At best it has systems and programs that it will keep running until it simply fails due to energy shortage or similar.

The solution would be to add programs that simulate this behaviour, but that is kind of the opposite of what this type of change is trying to achieve. It would be likely that these people would look for a "superior" behaviour simulation that gives them the best results in productivity for example, meaning the robots would all become more and more similar to each other as they would also copy knowledge, skills and capabilities off of each other. Within a short period after such a change the person they were will be a fraction of the uniform robot that is layered on top of it.


What about the teleporter problem?

Uploading your consciousness into a robotic body might even turn out to be impossible. How will the uploading be done anyway? Destructively, destroying your brain in the process? But what if the brain wasn't destroyed instantly? You will perceive that a robot with your memories walks away, and then you are killed. You die. You aren't uploaded. You are dead, while a robot emerges which is merely emulating you.

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    $\begingroup$ Yep - this is one of my recurring nightmares that I will see my new robot-self starting its new life while I finish mine in my organic body. $\endgroup$ Mar 2, 2020 at 18:05
  • $\begingroup$ This is the reason my preferred method of uploading is systematic partial replacement of brain tissue. Each section of my brain is replaced bit by bit with artificial components until there's nothing organic left. Then I have a robot brain that at every stage has been a conscious human mind. $\endgroup$
    – Ruadhan
    Mar 3, 2020 at 9:11
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    $\begingroup$ @Ruadhan Reminds me of the "Ship of Theseus" problem. When you replace every single component of a ship at least once and not a single original part remains, is it still the same ship? Unfortunately it's impossible to answer this question for consciousness, because we do not yet understand what consciousness actually is in a physical sense. $\endgroup$
    – Philipp
    Mar 3, 2020 at 18:41
  • $\begingroup$ I don't see how this is a real problem. Every time I go to sleep, my "thread of consciousness" is broken. How do I know that I'm the same person when I wake up each morning? How do I know that I'm not just a flesh puppet given all the memories of previous me? As long as the emulation is perfect or good enough and we don't have any supernatural "souls", you can argue that being killed and uploaded is no different than going to sleep. $\endgroup$
    – Dragongeek
    Mar 3, 2020 at 22:47
  • $\begingroup$ @Dragongeek : that's not the same. The robot situation would be like going to sleep, then waking up, then seeing another person resembling you waking up and walking away, and then you being dragged away to be killed. (maybe the time between these events is short enough that people witnessing others undergoing this procedure don't notice it, so they are confident that they will be transferred into a robotic body, while in truth they are just going to be killed and a different entity will be created - and whether that entity has the same memories is irrelevant) $\endgroup$
    – vsz
    Mar 4, 2020 at 5:05

A man can create a robot, but the other way around is impossible. Everything we create is just to make our lives better, or to help us things easier/faster, to live longer.

- Reproduction of humans. Once the last human is gone, we are gone forever.
- Robots will never be capable of having such "elastic", natural movement.
- Can you imagine a life where people look almost the same? That would be so boring. Lack of diversity is boring. Can you fall in love with a robot or any other "thing" that lacks emotion/feelings?

- Security. Most important, when a common connection is used(e.g internet connected parts)
- Nothing lasts forever. Not even metal or any other stuff. There is something that can destroy something else. We might live longer, but not forever.

  • $\begingroup$ I'd question the "elastic" movement remark, since human beings are already robots composed of self-assembling nanotech machinery. Even in the near term, though, with more traditional 'metal robots', we're already developing robotics with more organic style locomotion. See electroactive polymers (basically artificial muscle fibers) and soft grippers that surround and deform around an object and then become rigid, somewhat analogously to the palm of a hand gripping. $\endgroup$
    – Dan Bryant
    Mar 2, 2020 at 16:01
  • $\begingroup$ @DanBryant Yes, we are close to some very fluid movements, but I really don't believe we will ever create anything as perfect as we are as humans, for this matter. I wonder, from time to time, how easily we process and transmit the information from the brain to our parts, and it amazes me how complex we are, yet we focus our attention to create other things, loosing the bigger picture. We already have a lot, but we are just chasing our "tail". $\endgroup$
    – n1kkou
    Mar 2, 2020 at 19:22
  • $\begingroup$ "elastic" - so that's what the kids are calling it these days. $\endgroup$
    – Mazura
    Mar 3, 2020 at 0:27
  • $\begingroup$ @Mazura pretty mature remark. $\endgroup$
    – n1kkou
    Mar 3, 2020 at 7:53

Quick overpopulation and war.

"If you can upload yourself into one robot body, why not 1000?" https://worldbuilding.stackexchange.com/a/170102/581

You know those weird cults that just breed as much as physically possible? They can now copy-paste themselves. Uh-oh.

Every sufficiently rich person now has the option of converting wealth into copies of themselves. Being betrayed by a copy is always a risk, but a few individuals with weird minds will have perfectly loyal armies.

I doesn't matter that the average person wouldn't be interested. A few outliers will suddenly become a lot. The normals will try to stop them while it's possible. The replicators will take refuge in any contry that doesn't actively persecute them. And when that fails, they'll fight with the numbers they already amass.

War will be almost inevitable, but not completely. A quick worldwide consensus could build before any replicators can make a stand against existing governments, assuming reproduction is slow enough.

If that happens, or if the war is won by the normals, who still want a society close to what came before, there's a remaining issue: They'll have to restrict reproduction. There are very good reasons why societies on the freer side of the spectrum have a taboo against restricting reproduction. That power gets abused every time. Yet we'll have to try again.

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    $\begingroup$ "...why not 1000?" - because they aren't free. Do you have enough money, materials, workers, and know-how to make a thousand or a million copies? Surely nation-states would have those resources and war between those nation-states would inevitably happen. But that's not much unlike where we are now. $\endgroup$ Mar 2, 2020 at 18:03
  • $\begingroup$ @Tracy If they're remotely close to accessible for the median earner, then the truly rich can afford millions of copies in the least. Also keep in mind that the copies can make money to buy new copies. $\endgroup$ Mar 2, 2020 at 19:09
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    $\begingroup$ True. But isn't that the same with guns and people right now? A median earner can buy several weapons and hire an assassin or two or three - see the latest 48 hours for their investigation into the dark web. The truly rich can afford to go buy a bunch of guns (or build a factory to build guns) and create their own personal army to pursue their interests. The reason they don't is that they know law enforcement and the military is far larger than their personal army. And obviously when the robots are still pricey, the military will be first in line and will always have a numbers advantage. $\endgroup$ Mar 3, 2020 at 3:23

What about everyone else?

Here is a list of problems that could occur if a minority population (or majority disenfranchised population) can't, or won't, 'upgrade.'

Class friction

'Upgrading' to a robot isn't free. It requires quite a lot in the way of resources and expertise. So, ostensibly, some people can't afford it.

How do these people react to being surrounded by nearly immortal rich people?

How do the nearly immortal rich people treat these organics?

Keep in mind, fully organic people can still have children, while ostensibly, the mechanical population can't.

Income disparity

Given a hundred, or two hundred years, an effectively immortal human could accrue an enormous amount of wealth relative to someone who only has a working lifespan worth of wealth to draw from.

Even assuming they're not interested in building a financial empire, a mechanical human's operating costs are just so much lower than a standard human's. They have no need of food or shelter, or possibly even transportation.

They don't need to sleep, either, and they don't feel fatigue. They can work 80 weeks and still have plenty of time for hobbies.

Seeing this, the income gap between mechanical and biological humans must be extremely severe, and the wealth gap between them will only grow as time moves on.

Medical Treatment

At what point does it become more cost effective to simply replace a failing human mechanism with it's mechanical counterpart? What happens to anyone who can't afford that? What happens to medicine in general if the solution to most medical problems is just replace the part? Would anyone bother training in how to treat diseases, infection, or any manner of other medical conditions? Even if the knowledge doesn't become lost, the skills and practices might be.

What does that mean for people who haven't, can't, or won't become mechanical?

Disease and pollution

An largely mechanical populace no longer has any incentive to maintain basic sanitation. Machines don't catch colds. Similarly, toxic substances no longer pose a serious threat to a large percentage of the population.

Why bother addressing these problems if they're a non-problem for most of humanity? Or, at least, most of humanity that donates to political campaigns.

What does that mean for anyone left behind?

Food and agriculture

Making sure everyone stays fed requires a lot of people working together. At what point does the economy that supports world wide agricultural industry start to collapse? Note, currently, in order to make agribusiness profitable, most governments make heavy use of tariffs and subsidies. A minor sea change in how important governments believed these programs to be could cause widespread famine among those who are still biological.

Workplace safety and labour laws

Tons of people are now made of metal and don't need to sleep.

Also, lost limbs are replaceable.

This may cause drastic shifts in what is considered an acceptable amount of money to spend on ensuring occupational safety and reasonable working conditions.


1) If you make a backup copy of your own mind/body, does that backup copy have the same rights as you? Does it have every right to demand that it not stay in storage and instead live in your house?

2) People of different levels of income might be able to afford different levels of processing hardware. It could become the case that a billionaire links a remote server farm to their mind and now has thousands of times the processing power of the average person. Would they dominate politics? Would they outsmart one businessman after another and eventually gain a monopoly on all industry?

3) A whole new kind of racism. Technological humans may look down on biological humans as inferior. Biological Humans may treat Technological Humans as merely machines.

4) If people become machines they probably don't need to eat, so all food production ends. Ordinary farm animals that are not well suited to living in the wild become endangered or extinct.

5) Robotics today are less energy efficient than the human body. For example the human body typically consumes many times (probably about 10X) less energy when walking compared to prototype walking robots of today.

6) Engineers can create designs much faster now that they can directly input designs from their mind into the computer, rather than using a keyboard and mouse. The rate of technology development now accelerates drastically. Now no-one can keep up with learning all the tech that comes out seemingly every day.

7) People may become very reliant on internet access. They can now access any information on the internet just by thinking about it. It sort of becomes like the way we access our own memories. It becomes hard to tell what is your memories and what is external information. People become so reliant on network access that they are unable to function when they get stranded out of range of a good signal.

8) Many people may choose to just live in virtual reality.

9) Its probably the end of sports as we know it. The bodies of pro athletes would need to be standardized in some way, like the way a field or a ball is. Otherwise things could become quite unfair.

10) No more handicap parking at the store. Not really a problem, but at least a possible change.


Intelligence explosion.

One rich and intelligent engineer, let's call him Elon, will devote all his efforts to making himself smarter. This is not possible with a classic biological brain, but it can be done with artificial hardware and software. As he gets smarter, this process gets faster, until the rest of humanity are like mice at his feet.

This Singularity might be good or bad for the normals; there's no way to know until it arrives.


I almost feel that humans, if they became robots, would be rendered braindead eventually. This is because the human brain can only hold a limited amount of information, and even if you transferred consciousness digitally, it would still remain the same.


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