In particular, the gray-goo scenario may be a distraction from the real issues when one considers that while a vision of global destruction caused by endlessly self-replicating machines is an entirely hypothetical situation, the second law of thermodynamics presents a clear and actual threat which is scientifically known to be happening right now, constantly and everywhere in the universe. The second law of thermodynamics states, essentially, that entropy exists everywhere constantly, and is irreversible. Entropy, in turn, is the tendency of energy to transform into forms which are not useful because of homogenization. Energy only comes from difference: If there is a difference in temperature, pressure, or voltage between two points, that difference constitutes energy which can be employed to perform useful work. If two points have the exact same temperature, pressure, or voltage, then there is no energy present there which can be used in any way.
It is believed that entropy will inevitably destroy the entire universe, because as time goes by, all energy becomes increasingly homogenous. That includes matter, because matter is just another form of energy. (Recall Einstein's famous equation e=mc^2, which says not much more than that energy equals mass.) The process happens fairly slowly from the human perspective, but with time, everything inevitably becomes transformed, one way or another, into a form of energy (usually heat) which is stable and thus not useful because it cannot do anything. As far as we can tell, this process is unavoidable and irreversible. Its usual name is "the heat death of the universe", but you can think of it as simply being a state of complete, uniform consistency, where there are no differences between anything anywhere, because all matter has become blended into a homogenous mass, and thus there is no usable energy anywhere.
While the process of the universe becoming destroyed through entropy proceeds slowly enough that we cannot generally perceive its occurrence, there is a similar process occurring within humanity which proceeds more quickly, and which people have taken notice of. One might call this phenomenon anthropological entropy, the process whereby humanity becomes one solid, undifferentiated mass instead of a variegated group of individuals.
Some people may interpret this idea from a racial perspective, specifically with regard to an idea which is more current now than at any other point in recorded human history, namely the idea that the different human races will blend together with time. As migration between continents becomes more common and interracial people are born as a result, there is a widely-believed idea that in the future, the current different races which are associated with different parts of the world will begin to disappear and blend into one more or less global human race. Like the scientific process of entropy, this process is probably inevitable, because one thing you can't stop human beings from doing is having sex with each other. But I do not merely mean this idea in a genetic, racial sense, but more generally in a cultural sense. The process of racial blending takes a while; it will probably still be hundreds of years before physical differences between races are eliminated, where there are no more "white" or "black" people left on Earth. Indeed, it might never happen. Who knows? What can happen very quickly--within a single generation of human lives--is entropy of opinion and culture.
In most parts of the world, human societies have carried on various traditions for thousands of years. There are ways of life which different civilizations have established and passed on from ancestors to their descendants over countless generations. What happened very quickly when globalization became a thing, however, is that these traditions were wiped out and replaced with one global monoculture. When intercontinental air travel, television, and the Internet became globally available, the whole world said, with one voice: "We're not interested in what our ancestors have done for thousands of years. The only thing that interests us is watching entertaining television shows and talking to friends about light, entertaining subjects. That is what we live for. That is our meaning of life, and everything else is completely irrelevant to us". This change happened within a lifetime; there are people alive today who remember a time before television and the Internet. It won't be long before those people die off and those days disappear from living memory. When that happens, all that will remain are the results of cultural entropy, as other types of culture disappear from the universe and a single, homogenized culture remains.
Like the other types of entropy, this process was perhaps unavoidable. When different cultures have contact with one another, they will inevitably influence each other, and if the contact is constant, differences between those cultures will begin to disappear. Mass international media like the Internet is a giant steamroller that crushes and blends all cultures into one. But a more controversial question is whether this should happen: Should different parts of the world maintain their own local, distinct cultures which are different from others, or should humanity be cast into a universal melting pot from which there is no escape?
The end of World War II changed humanity forever. War has existed since before recorded history, but for the first time in history, there was and is a weapon so powerful that a single nation could use it to destroy all of humanity. This forever changed how politics sees war: Previously, war was sometimes seen as heroic and noble, and even when it was undesirable, it was often seen as unavoidable, a necessary evil. Now, the spectre of nuclear weapons has changed war into something that must be avoided at all costs, because instead of resulting in a few million dead soldiers on a battlefield, it could rapidly and suddenly lead to the annihilation of all life on Earth. War is no longer a game played between nations on a battlefield; it's become a global concern, because two people's war could become everyone's doom.
The problem is that conflict is baked into humanity. It is human nature to fight. People often disagree on things and they may have valid things to fight about, but even if they don't, they will make up new things to fight about just because they have a psychological need for an enemy, someone or something to fight against. This problem is compounded by the fact that human beings are naturally ideologically diverse: People value things inexplicably and irrationally, which means there can be no reasoned discussion or union between them because there are no logical, rational reasons for what they want in the first place. If you make a list of highly controversial questions, everything from "Should same-sex couples be allowed to get married?" to "Should racial epithets be protected under freedom of speech?" to "Which diseases should children be vaccinated against?" to "Should gasoline-powered vehicles be allowed in city centers?" to "Until which month of pregnancy may abortions be performed?" to "What should children be taught in schools?" to "How should the government regulate how people build their houses?" to "Should there be a national language?" to "Should parents be allowed to teach their religion to their children?" to "How much money do we charge the tax-paying public for health care?", you will rapidly find that you can fundamentally and irreconciliably divide any group of people, to the point where those people are willing to fight for what they are convinced are their "correct" answers to such questions. One fundamental fact about human nature is: You will never, ever get a large number of people to agree on any list of questions about fundamental values. This being the case, trying to unify humanity is a fool's errand, a dead end which can never go anywhere because it is nothing less than trying to change fundamental human nature, like trying to make a field of cows meow instead of moo.
You can be certain that this reality has not escaped the notice of governments around the world. These administrations are now faced with an impossible task: Prevent people from fighting, when they are inherently built for ideological conflict. Conflict between people must somehow be managed, because it cannot be eliminated, and so various administrations have come up with various ways to ameliorate people's need to have an enemy. Fictional enemies are surprisingly good at doing this: If you have an obvious "bad" person or group in a fictional movie or TV show, this provides the public with a popular target of hate, something which people can direct their rage at in a fairly harmless way, since the person or group being hated is, obviously, fictional. More recent technology makes it possible to incorporate such figures into video games, which is even better because it allows people to personally take part in the fight against such figures, making them feel like they are virtuously fighting a worthy battle against some enemy without actually affecting anything in the real world.
Of course, some people are smart enough to realize that fighting enemies in a video game doesn't change anything in the real world, and so governments also need to create popular real-world enemies for the public to hate. As I write this, Donald Trump is perhaps the most popular target in the world. Trump has done humanity a great service by giving human beings someone to hate at a time when they really need it; in our current political environment, everyone can safely say that they hate Trump and that he is the cause of all our problems, and people can thus feel that they are doing something good with their lives and "fighting the good fight" without having to consider that they are not actually doing or changing anything. If that isn't good enough, there are plenty of other politicians and other media figures, both domestic and foreign, who serve well as sponges for the endless hate of the general public.
Another popular tactic is to give people avenues where they can express themselves, and this is where the Internet serves as an endlessly useful instrument of governments around the world. Before the Internet was widely available, people had to resort to calling talk-radio shows in order to feel like they had a place where they could air their opinions, but now there are countless chat rooms and message forums on the Internet where people can vomit out as much personal opinion as they want in the carefully-maintained illusion that someone actually cares about what they have to say, then go to bed happy that they have made the world a better place by writing what they think to an invisible and imagined audience. The Internet acts as a huge steam valve for global humanity, allowing people all over the world to convince themselves that they have a voice, and that if they scream loudly enough on the Internet, surely someone will hear them and believe what they have to say.
Inevitably, however, someone lifts up their head and looks around, and realizes that discussions do not lead to anything. You can debate and discuss and consider and talk and protest as much as you want, and all of this changes the state of the world exactly as much as if you had done none of these things. Sooner or later, someone is going to say: "You know what? We're tired of discussing and debating and negotiating and trying to be understanding and trying to get people to understand us. It hasn't changed anything. Talk is cheap. Only action brings results." This is true, of course, but exactly what form that "action" takes depends on how far someone is willing to go and how much they have to lose. In our current world, there is still a relatively large portion of humanity with a decent standard of living who would be afraid of losing that comfortable lifestyle, and so they restrict themselves to marching down streets while chanting slogans and waving flags. This idea of "action" is also relatively harmless, and even if it does sometimes result in a few assaults, broken windows, and looted stores, people generally eventually get bored with it and go back to watching television and sitting around talking about nothing.
Much more dangerous than anyone with a comfortable life which they're afraid to lose is the animal who's backed up against the wall, the vicious beast who has nothing left to lose and is perfectly willing to do any insane act for any reason, ostensibly as an "act of protest" but often just because people are bored and don't care whether they die anymore. A truism which people have generally not been willing to embrace is the fact that violence is the only thing which motivates people. You can ask, beg, request, plead, reason, debate, negotiate, and threaten, but all of this will bring you exactly as much success as if you hadn't done so. Sooner or later, people reach the conclusion that only through violence can people ever reach their social and political goals. Violence and force are the only things which have ever created change. You can tell people to do something and they'll ignore you, but if you start shooting people or putting them in jail, they're more apt to heed what you have to say.
Now, you might say that you don't want to live in a world like that, a world where both governments and activists use violence as their first resort rather than their last resort. You wouldn't be alone in that; not many people want to live in a world of constant warfare where everyone is willing and able to use physical violence to achieve whatever goals they might have. And so to try to avoid such an outcome, there is an ongoing effort to harmonize humanity not by unifying their opinions, but by getting them to avoid thinking about opinions at all. If there's anything which thousands of years of human history have taught us about humanity, it's that discussion does not create unity among human beings. Enemies do not sit down and talk out their feelings, then end the discussion by saying "You know what, you're right. I have so much more empathy and support for you and your ideals now!" They leave such discussions by saying "Your values and your goals are utterly incompatible with mine, and I am not willing to compromise on what is important to me so that you can claim a partial victory by getting me to compromise on fundamental and inviolable values. This discussion has only reinforced my belief that we cannot come to a compromise through discussion, and that force is my only option if I am to ever achieve what I most want to achieve with my life". You can't unify human beings by getting them to talk about their most fundamental values, their visions of "what the world should be like", or "what people should be living for". So how do you unify humanity in that situation?
The answer is surprisingly simple, but what's downright astonishing is how effective the solution is: Get people to avoid talking about things in the first place. You can distract them with things like television and video games, but long-term, an even more effective solution is to simply convince people that such things don't matter. After all, a person who walks away from a movie is probably going to start thinking about things after the movie, and so the movie can only get them to stop thinking deeply for a couple of hours. By contrast, if you convince people that things like "values" and "ideals" aren't important at all, you can create a human society which is more stable in the long-term because it doesn't value anything.
This is the solution which governments around the world have been rushing to adopt in the years since World War II: A solution which teaches everyone in the world to uniformly believe that "There is nothing important and no value in the world other than just doing whatever you feel like doing. Have fun and enjoy life and don't think about anything else". This is the mantra which is being programmed into nearly every person in the world as part of a global project to pacify humanity.
Now, I am not promoting some conspiracy theory here: I do not mean to say that some shadowy cabal of hidden figures has concocted this plan together. Maybe they have, but if they have, I am not any more aware of any such conspiracy than anyone else. What I do know is that this is what's happening in practice. It may very well be that this outcome is unintentional; I am not saying that anyone is deliberately trying to homogenize humanity, I am merely saying that that's what's happening, whether anyone wants it or not.
From an evolutionary perspective, amorality is the best standpoint to take in terms of survival. If you value anything very highly, you may be willing to die for it, and that often leads to lethal actions taken by people defending their values. By contrast, if you turn humanity into a group of amoral creatures who are really just living to be alive but don't actually care about any high-minded ideals, this promotes long-term survival of the species because nobody has anything to fight over. Just become born, then become dead. That's all you have to do. Simple, right? Anyone can achieve that.
One might suppose that intelligence can hardly exist in such a world, but in fact, pure intelligence as a logical construct is desired, because some people will still be needed to write computer software and such. It's okay to be intelligent in terms of being good at math and science. But people must be discouraged from asking deeper questions about human nature. Above all, people must be prevented, by any means possible, from wondering why they exist or thinking about values of any kind. Value must not exist in the perfectly peaceful human world, because values lead to conflicts. Intelligence is okay, but only the kind of intelligence that lets you write computer software or design an energy-efficient building. Reading of literature, especially Philosophy, is to be stringently avoided, and any fictional stories must be carefully sanitized to act as completely fictional tales with no relation to the real world, or, if there is a villain in the story, the only permissible villains are people with personal values, because it is important for humanity to understand that personal values cannot and must not be allowed to exist. Personal values are bad; they lead to conflict and misunderstanding and war. Just do your job and watch your TV and if you say something, make sure it is something light and entertaining and amusing. That's life.
Have you ever noticed that when you speak with someone who agrees with you, you don't learn much from the discussion? Two people who agree on a subject can only nod and say "Yes, I agree with you". Not much further insight is generally possible from such an encounter. You typically learn the most when you speak with someone who disagrees with you. In particular, you can only gain insights into human nature by talking to people with whom you disagree. When you ask people why they think the way they do, what values they hold important, and what motivates them to live and act the way they do, then you find out about human nature. But these kinds of interactions are the most dangerous possible interactions in the peaceful human world, because they would begin to expose differences and disagreements between people. The only interactions which can be allowed between people are those which make conversation difficult: Loud music concerts are perfect, because in such a setting, it is very difficult to have any kind of conversation in the first place, and if people do talk, it will generally just be about the music, which is something people can share and enjoy together since they wouldn't have gone to that concert if they didn't want to enjoy that music in the first place. Other social venues are okay, but only those which encourage light, entertaining conversation. Deep thoughts or potentially controversial topics are to be avoided to the greatest extent possible, and if anyone dares to be intelligent or curious enough to raise such a theme, the subject must be changed immediately. Otherwise, human beings risk gaining a deeper insight into human nature. Human understanding must not be allowed to exist in a world where everyone is harmonious and unified. If someone disagrees for any reason, the only way to deal with the situation is to categorize that person as bad and evil and unwelcome, someone to be fought by any means possible, lest they disrupt the unity and harmony of peaceful human society.
Such is the future of peaceful, harmonious human society. Anthropological entropy ensures that all human beings will eventually be brought together in such a way that differences between them are not erased (because that is impossible), but rather hidden from sight so that they seem to disappear. As long as they escape people's notice, people are not likely to think about them, and so the great dream of peace on Earth can finally be realized as the world's human biomass congeals together into one blurred, dull mass of homogenized humanity.