Skip to content

Fallout 4: Why does The Institute replace people with synths?

Warning: Fallout 4 spoilers ahead!

I’ve been playing a lot of Fallout 4 recently, and there’s one glaring question that I find hasn’t been addressed: Why does the Institute replace people with synths?

First off, does the Institute replace people with synths? You hear rumors in the Commonwealth, but lots of people are quick to say that it’s a myth. Once you reach the Institute you see that the Gen 3 synths really are indistinguishable from humans. You can also find on a terminal a list of people that are informants for the Institute, which I suspect means people that have been replaced by Synths. It seems much easier to replace these key people with synths than it does to simply convince them to inform for you. Members of the Institute are quite adverse to going above ground, and I can’t see a Courser wanting to do much talking. In my travels in the Commonwealth, I have also come across someone being replaced by a synth in a random encounter. A person was pointing a gun at a person that appeared identical to them-self, kneeling on the floor with their hands raised. Due to my character’s high charisma, I was able to convince the suspected-synth that I could be trusted and that they should just tell me if they were a synth. The synth confirmed that they were a synth, and asked me to help them kill the other guy so that he could take over his life. I elected to let the human shoot the synth.

So, why does the Institute do it? Through heresay in the Commonwealth, it seems that synths act as sleepers, pretending to be humans until they suddenly kill everyone. Perhaps the most famous case is that of Mr. Carter in Diamond City. In 2229 (some 60 years before the player visits Diamond City), Mr. Carter visited Diamond City. This was a time before the fear of being replaced by a Synth had spread. Mr. Carter reportedly had arrived in town earlier that day and had been quite friendly, setting people around him at ease. Come evening, he sat at the bar where Takahashi now sells his noodles, and ordered a drink. Without warning he opened fire on the residents around him, in an event that has become known as the “Broken Mask”. Piper’s newspaper, Publick Occurrences, contains an account of what happened from the point of view of Eustace Hawthorne, one of Diamond City’s oldest residents. She recalls that Mr. Carter had had several drinks by this point and seemed quite drunk. Suddenly, the smile left his face and his cheek started twitching. As he opened fire, he showed no emotion. He was gunned down by Diamond City Security, who discovered that he was full of plastic and metal. Eustace commented that he was one of the early model synths. It seems safe to assume that Mr. Carter was not a gen 1 or 2 synth for people to have not recognised him as non-human, but people seem to struggle with identifying gen 3 synths (i.e. they seem to be made of blood and flesh, like a regular human). Does this mean that there is some sort of in-between gen? 2.5, perhaps? Maybe low light and careful clothing allowed for him to pass as human? Surely he would have needed to wear some form of eye-wear to cover his glowing eyes, if he was a gen 2. There is a quest in which the player has to meet Bonnie, a ghoul, in Diamond City. She is able to enter Diamond City while wearing a full face mask to hide her appearance (as ghouls are not allowed in Diamond City). Perhaps people are not suspicious of those wearing very covering armor? How hard are synths to detect, really? Killing people that are as it turns out gen 3 synths will yield a “Synth component” item upon looting. This seems to be the only confirmation of their nature, their corpses look otherwise human. Eustace’s description suggests that there were more mechanical parts to Mr. Carter than just a singular Synth component, however.

Perhaps the timing of the Broken Mask is significant? When the player meets Shaun at the Institute, he is aged 60 (having been 1 year old the last time he was seen by the player). Broken Mask takes place 58 years before the year in which the game is set. It is discovered that the Institute took Shaun as he was free from radiation, and the contamination seen in the Commonwealth. Somehow, his pure DNA was able to be used to create more perfect gen 3 synths. Are the timings of these events a co-incidence, or was Mr. Carter a prototype gen 3 created using Shaun’s DNA? Perhaps he malfunctioned due to being a prototype, causing the shooting. There did not seem to be any reason for him to open fire. Perhaps early synths were not designed to be able to deal with alcohol. As the Institute keeps itself separate from the surface (apparently even cultivating and synthesizing their own food), perhaps they do not regularly ingest alcohol and so were not prepared for their synths to deal with the affects of it? Perhaps Mr. Carter malfunctioned for no real reason. Perhaps it was not a malfunction, and the shooting was intentional. Maybe the twitching of the face was a sign of Mr. Carter attempting (yet failing) to rebel against his coding, to show some humanity and not shoot people?

The other main attack on the Commonwealth by the Institute that is mentioned within the game is the massacre of the Commonwealth Provisional Government (CPG), occuring at some point in the 2200s. The CPG was an attempt to create some form of government within the wasteland, drawing representatives from every major settlement within the Commonwealth. At the first convening of the CPG, a synth institute attended. This synth murdered everyone in attendance. The idea of the CPG was abandoned after this. Father (Shaun) comments that the Institute had tried to help create a government in the Commonwealth. He states that it ended in bickering and infighting, and that it was a disaster. It seems that the matter of what actually happened at the CPG meeting is never properly addressed. Perhaps this was because all in attendance were killed (bar one synth, potentially). If a representative from ever major settlement was sent, it seems that a large number of people were in attendance at the CPG meeting. Due to having to travel the Commonwealth to reach the meeting, it seems likely that people were armed. If an Institute synth really did massacre everyone on it’s own, it seems unlikely that it would have been a regular synth. Your average gen 1/2/3 synths do not hold up very well in combat. Perhaps it was an Institute Courser that was sent to the meeting. However, Coursers are not famous for their diplomacy skills. Did the Institute attend the meeting with the intention of killing everyone in attendance? This seems like it would be a counter-intuitive action on the Institute’s part. They want humanity to survive, and forming a government seems like it would be a first step in the direction of re-forming a civilization. So why, then, would the Institute want to prevent it? Did they want to be the Commonwealth’s only shot at civilization, being the only ones to form/run a government? Or was Father telling the truth? Perhaps the Institute did want the Commonwealth to form a government, and they did simply sent a synth to observe the proceedings and potentially help shape them as needed. Perhaps fighting did break out among the attendees, leading to those in attendance to massacre each-other. Perhaps the synth did not partake, perhaps it did. Perhaps the synth survived, perhaps it did not. The exact date of when the CPG massacre occurred is hazy, but perhaps it occurred after the Broken Mask incident. It could have simply been blamed on synths due to the building fear of them, without a synth actually being responsible. Due to all accounts of the event being rumors and hearsay (I don’t suppose anyone took minutes during a massacre), it seems that this will remain an unanswered question. If everyone in attendance did die, it seems that this would hamper the availability of the truth on what happened during the CPG massacre. There does seem to be a tendency to ascribe more malice to synths than they actually display, however. The times when synths have indisputably massacred people (such as the village inhabited by Jacqueline, who found some work that the Institute was interested in) seem to have been forgotten, whereas the times in which the synths may not have been completely at fault are remembered. I feel that the following cartoons summarizes the public attitude towards synths quite well:


During the game, you will have the chance to meet various synths that have escaped from The Institute (such as those assisting the railroad), and those that have been turfed out (such as Nick Valentine). Why is the Institute happy to abandon some synths, but not others? Do they intentionally release some synths? For example, take Nick Valentine. Nick has a very strong sense of right and wrong, with his memories/personality having been lifted from a pre-war policeman. The Institute seems to have no interest in recovering him, having wiped his memories of the Institute and set him free. It seems likely that Nick cannot be unique. Perhaps synths like Nick are a form of “public relations” action being taken by the Institute? Escaped gen 3 synths seem to generally either become recaptured, or find their way to the Railroad. Synths encountered by the Railroad are given the opportunity to have their memories wiped, and their face redesigned. They are then implanted with fake benign memories, and turfed out in to the wastes to do as they please. By completing some Institute quest chains, you are sent out to assist a Courser in recovering such synths. One synth has become quite high up in the chain of a gang of raiders, and the Institute is very keen to recover them. Perhaps part of the reason that the Institute wishes to recover such rogue synths but is happy to have Nick (and human-replacing synths) wandering the Commonwealth is because of their attitudes. If it was discovered by the people of the Commonwealth that the leader of a gang of raiders was a synth, there would be even more paranoia about the Institute. A synth such as Nick however, is seen as helpful by the people of the Commonwealth, despite him quite obviously being a synth. This could lead some people in the Commonwealth to believe that not all synths are bad. It has certainly made me think twice about which faction I want to side with in the main story-line.

Coming briefly back to original question: why does the Institute replace people? There are no firm answers provided in the game. The dialogue options in Fallout 4 seem a lot more limited than they have been in past games, and so the cynic in me feels that simply no-one bothered to tie up that loose end because the limited conversation mechanics didn’t really facilitate the player asking so many questions. Other players have suggested that perhaps it was done so that the Institute feels like less of a morally grey faction. Perhaps if a good reason was provided by them for replacing people, the player would have been more sympathetic to them rather than them seeing the Institute as the “bad guys”. Personally, I still don’t 100% see them as the bad guys. Their use of gen 3 synths as slaves seems to be a major cause of their bad reputation among the player base. I’m still unsure how I feel about this. Synths escape from the Institute. If they are caught by the Institute their memories are wiped, and they are returned to work. If they are found by the Railroad, their memories are wiped and they are returned to the Commonwealth. True the Railroad technically gives the choice of having their memories wiped or not, but it seems to be a non-choice for the synths. They are wiped and given new memories. I would ask, how is this that different from what the Institute does? Both effectively destroy what was human within than synth, which to me defeats the purpose of that synth having escaped. They have escaped just to be destroyed, only their body is able to potentially move forwards. It seems odd to be so concerned about the body, when the existence/behavior of the synths prove that what is human is the mind. In essence, the Railroad frees the synth body, but not the mind. Does this mean that the Railroad is providing more of an assisted suicide service for synths, rather than truly “freeing” them? A new person is created using the body as a vessel, and this new person goes on to act as they see fit. This is perhaps why the Institute is so keen on recovering these synths (even after their minds have been wiped of any information about the Institute), because of their unpredictability. See my prior comments on the raider leading synth. I personally would have liked to see more Nick-style gen 2 synths in the Commonwealth. Synths that have left the Institute, but have retained their “humanity,” as it was before.

There’s no debate that the Institute replaces people with synths. The process can be seen in game, as previously mentioned. However, how do they replace people? To be creating full, biologically accurate copies of people, it seems that they would have to abduct people first to be able to create their copies. Confrontations can be seen in the Commonwealth in which a person has mysteriously disappeared for a few days, only to be accused of being a synth upon their return. There are also cases where people have disappeared to never return, with the Institute being the lead suspect in the disappearance. So why is it that when the player encounters a replacement, they witness the human in the Commonwealth directly confronting their clone? Did the human escape? It seems unlikely. It can be assumed that the Institute either made an error in the timings of releasing the copy (i.e. before the original can be removed), or perhaps they intend for the copy to dispose of the original them-self. Per Shaun’s abduction, it seems that the Institute needs DNA to create their gen 3 synths. Perhaps they collect a sample of the target’s DNA prior to abduction/disposal to create the copy, then send the copy in to abduct/dispose of the original? Perhaps the copy is dispatched without the “mind” of their target, and they have some method of copying their memories/knowledge during the abduction/disposal? It seems that this would be a very clumsy method of abducting/replacing people, however. If someone was to walk in on the replacement taking place (as the player does), it is obvious what it taking place, much more so than if the synth appeared as, say, a raider. Perhaps there has been a change in the method of original human disposal. From speaking with Virgil/looking at his computer terminal within the Institute, it can be found that the Institute was testing the Forced Evolutionary Virus (FEV) on abducted people. It seems like a nice way of taking care of the person being replaced to bring them in for FEV testing. However, after Virgil’s escape, it seems that the FEV testing lab has fallen into disuse by the Institute. So, why abduct people if you do not need them to be able to create clones? People from the wastelands DNA will have been corrupted by the radiation, is their DNA even used in the creation of the clones? Perhaps the Institute has other forms of bioweapons that they test on people, perhaps they have other reasons for wanting to abduct people. Perhaps the Institute no longer actually abducts people since they stopped testing FEV, instead having the synth copies kill the originals/dispose of the bodies as they see fit. But, would there be any real way of taking a copy of their memories in the field? It seems that the copy would absolutely need to be able to take a copy somehow to be able to fit in in the original’s place. The only place outside of the Institute that seems to be able to do manipulations of memories such as this is the Memory Den in Goodneighbor. It can be found out through the story-line that the Memory Den works with the Railroad to help implant fake memories in to escaped synths. In light of this it seems highly unlikely that the Memory Den would also be working with the Institute to help synth replacements to copy memories. Goodneighbor is also very anti-Institute, and it seems that someone dragging an identical copy of them-self through the town center would not go unquestioned. To me, it seems that the “live replacement” witnessed by the player may have been somewhat in error. It would be illogical for the Institute to abduct someone, copy their memories/grow their synth copy, then return them to the Commonwealth so that they can then be removed by their copy. It seems to me that the game developers wanted to absolutely confirm it in the player’s mind that the Institute does replace people with synths, and so decided to show the player a replacement without really considering the process that the Institute would be likely to use.

From the list found within the Institute, it can be seen that many key people have been replaced within the Commonwealth. It seems that people on this list are aware that they are synths, but there are also people (often unlisted) that may not be aware. You can also perform some investigations yourself by killing people and picking through their remains, or sometimes by following quest chains. Sturges, one of the first NPCs encountered by the player, drops a synth component when being killed. It is entirely possible that Sturges is himself unaware that he is a synth. He can help the player build the teleporter to gain access to the Institute for the first time, but as Father wanted to speak to the player this does not really suggest anything for/against him being aware of being a synth. As it is, there seems to be no way to know if he is aware of his status. A more interesting example perhaps is Paladin Danse, of the Brotherhood of Steel (BoS). Through continuing the main story-line, it can be discovered that Danse is actually a synth, and was not aware of this. When his synth status is discovered, Elder Maxson orders that Danse be killed. Danse himself requests that the player kill him, suggesting that he was completly unaware of his status. It is interesting to wonder when Danse was replace, due to his being completely unaware that it has happened. Was it some time before he joined the BoS, or was he replaced as a tactical decision once he joined the BoS? Surely there are better people to replace within the BoS, such as Maxson himself? Perhaps he is too well protected on the Prydwen for even the Institute to be able to reach. Danse being an unaware synth (as well as Sturges, potentially) points towards the Institute using replaced humans as sleeper agents. It is unclear if the Institute is able to passively collect data off of such individuals, or if they simply sit in rest until they are needed by the Institute. Self-aware synth replacements, such as Mayor McDonough of Diamond City seems to actively report back to The Institute. Having a synth be aware of it’s status as a synth seems to be a major security risk, and so it seems likely that if data could be collected via synths without requiring any action on the part of the synth, then the Institute would potentially operate more in this way. Then again, perhaps having McDonough be aware of the Institute/his position is more beneficial. It is commented by Piper that the Diamond City Security do not investigate reports of disappearances, most likely at the order of McDonough. Is having him steer people away from investigating disappearances really of benefit though? It seems to build paranoia among the people of Diamond City, and has even led to suspicions that he is in fact a synth. Terminals within the Institute suggest that they expect McDonough to not last much longer. Perhaps he has simply done an abnormally poor job, and that having synths be aware of their position is not necessarily a bad thing. Still, it remains hard to detect if people are synths, and even harder to tell if they are aware of their synth status. In the town of Covenant, the SAFE Test (which appears to be a copy of the GOAT seen in Fallout 3) is employed as a method of synth detection. However, it appears to be very inefficient. As gen 3 synths seem to be biologically very similar to humans (down to it being possible to “romance” them), their detection without killing them seems to be a difficulty. However, the synth components that they do contain seem like they would be detectable using methods such as x-ray technology. Old hospitals seen throughout the Commonwealth appear to contain x-ray machines, alongside x-ray printouts. This, combined with the knowledge of pre-war ghouls, makes it seem very odd that no-one has repaired an x-ray machine to working order. High technology seems to be possible within the wastes, from Vertibirds to Liberty Prime. True, Vertibirds were initially reverse engineered/rebuilt by the Enclave, whom are not present within the Commonwealth (that we know of, but there’s always room in expansions), and so most likely have not built anti-synth technologies. Still, it seems the the BoS is technologically on a level with the Enclave in Fallout 4, and so it seems bizarre that they would not be able to get an x-ray machine to work. The source of x-ray radiation within the machines seen in game may have been depleted due to the long period of time, but it seems likely that the greatest minds of the Commonwealth would have been able to come up with an alternative. Perhaps the game writers deliberately did not make the recreation of such machines canonical, as it would have made it too easy for the players to detect synths within the wastes. Then again, VATS can be used to detect if any settlers within the player’s towns have been replaced by synths, by inspecting their energy resistance levels. It can be useful for the player to clear out synths as in the event of synths attacking a settlement, synth settlers will join in with the attack on human settlers. Perhaps everyone should just get Pip-boys and VATS for detection purposes.

So, why does the Institute replace people? Despite all of my thinking on this, I really don’t know. Perhaps if the Institute could replace the majority of the people (as seen in The World’s End movie), they could facilitate a sort of peace in the wastelands. It seems that people would not be very happy with this. It raises the age old question, is it better to be free than safe? Perhaps the reason that some synths attempt to escape the Institute is because they believe that the former is better than the latter. It does seem to be human nature to believe this. Perhaps the Institute replaces people simply as sleeper agents in case they need to infiltrate an organization, such as the BoS. Perhaps they replace people to be able to manipulate the public interest, such as in Diamond City. Perhaps they do it to test how high-functioning their synths are, that they are able to live alongside humans, disguised so well that even their loved-ones struggle to tell them apart from the originals. Perhaps they do it simply because they can. Either way, I am disappointed that the player is not provided with more information on the “why” of the Institute’s activities. The player has the option to become the leader of the Institute, and even doing so does not provide the player with more answers. I can only hope that in the future expansions the story is wrapped up a bit better than it has been so far.

Published inGaming


  1. Ethan Ethan

    very insightful! i had wondered these same questions myself , and also Sean (father) says that some synths escape and they don’t know why… did id miss a further explanation or did bethesda just not give us one?

  2. ajacksonian ajacksonian

    My thoughts go along the lines of yours, particularly during Human Error. By then I knew that Gen 3 Synths drop Synth Components and that seemed a reliable way to find out if someone was a Synth. If you are a pre-war individual with any experience of pre-war tech, then you should have some understanding of how an x-ray machine works. And it isn’t as if there is a lack of nuclear material around, either.

    As to the plans for replacement it is a slow, multi-step process from what I can figure out. Getting the Gen 3’s up to snuff where they can still be controlled is a hitching point with the Institute, and you can eavesdrop on such Synths inside the Institute already showing independent behavior.

    The use of humans out in the Commonwealth is a way for the Institute to keep tabs on the Synths they send on missions that require no attention, and those gone rogue that require SRB intervention. This is an ersatz INTEL network and when coupled with the spying cameras the Institute has in the Commonwealth, allows for the identification, tracking and dealing with rogues. If a Courser can’t take down a rogue, then there is little that can be done as that rogue is either more capable than any Courser or has friends able to deal with them and are not worth further resources to go after them.

    The long-term dealing with humanity is a two-fold operation and the first part is humanity winnowing and removal via FEV created beings like Super Mutants. There must be a separate group from the Institute working on this project post-Virgil as newer and more powerful Super Mutants continue to arrive post-Institute. That would make a great DLC!

    Part 2 is harder, but Virgil points to the FEV used by the Institute as different than that seen in prior Fallout games: it can be created with a weakness for reverting individuals. Once most of humanity is gone, then the Synth infiltration will be much higher, and then removing the Super Mutants and rest of humanity is a relatively easy affair as the sleeper Synths are activated, and higher capacity Gen 1 and 2 Synths are sent in to go through removing human survivors in detail, perhaps with a Courser to back them up as field commander.

    This would explain why Virgil really left, why the Institute is running its own Super Mutant creation system: it is all looking towards a long-term replacement of humanity and human necessary animals. How they expect to deal with Deathclaws is problematical, however, as well as the other mutated creatures filtering in from the wasteland. They do have plans for better farming (as seen at Warwick), but that isn’t going to do very much to bolster a population that, of necessity, must be manufactured (although Deacon does raise an issue of Synths having children who, perforce, cannot be Synths…another great DLC venue, really).

    Danse is, apparently, a rogue with a memory wipe, but one the Institute tracks as they have the reset code they can use on him in battle. One or two vital commanders suddenly being taken out can turn the tide of an important fight, as the Hashisham demonstrated back in the day. I would sorely like to recruit him to the Minutemen if he can be saved, and just give him a set of headphones made to keep ‘factory reset code’ as a silent translation so that he just can’t hear those words in that order. Great as a companion, but priceless as a trainer for Minutemen volunteers…heck, I got sets of armor I don’t use and if I can team him up with the Atom Catz, then the Commonwealth has the potential for a PA fighting force that can secure it permanently with or without the BoS. That would make a great DLC.

    That’s what I’ve garnered from one play-through, and I took my time doing it as there was so much to see and do. Plus I got seriously distracted with side-quests. I would love to wander the Wasteland as The Silver Shroud, righting wrongs and handing out justice to the wrong-doers. Just let me use Ballistics Weave Mk.V on the costume and hat and I’m set. That would take a ton of voice acting, though, so while a potential for a DLC, it really is another game in and of itself. Just set up one Companion to be Madame Mystery…or put that as an alternate for an NPC like Magnolia (if you can tear her away from the stage…although she would be great on SS Radio come to think of it…calling Lynda Carter!) for it.

    There are tons of loose ends to Fallout 4, but the main theme appears to be one of human eradication and replacement with Synths by the Institute with only a small number of humans left to control the thing. I mean, that worked out so well in Vault 75, didn’t it? Almost like that was a giant hint dropped in your lap or something.

  3. Jeccica Dellow Jeccica Dellow

    With the presence of Nick valentine in the commonwealth after the CPG (you learn this through some dialog with him as you improve his affinity) it is unlikely that there were any gen 3 synths were in existence at the time of the massacre as Nice seems to have been a prototype for a cognitively enhanced synth project- a prelude to the gen 3.
    As the “Broken mask” was an event involving a gen 3, cpg likely predated “Broken mask”

  4. Daryl Daryl

    You learn Nick’s story in the far Harbor DLC, where he’s revealed to be the brother of DiMA.
    After Playing through all four possible endings, I have to admit there seems to be no reason to save The Institute. Their reason to exist isn’t compelling enough. I really wish Bethesda would have made their mission statement more credible. Or… given them any mission statement at all. I have no clue what their motto would be beyond, “Best Hope for Humanity”. Seems kind of thin.


    If you side with the Institute, when shaun dies besides his coat is a holotape that is a woman scolding a scientist for releasing the synth as it was a prototype into diamond city, therefore causing the broken mask. Hope this helps!

Leave a Reply

Your email address will not be published. Required fields are marked *