The purpose of the story “They” is to question reality. It makes the reader wonder whether the world that they know is actually what we think it is. In this case the world that the nameless man lives in is all a “stage” to a point, all created with fake people (it is hinted at that they are machines) and all made for the purpose of keeping him captive for some unknown reason. The idea that we could be imprisoned within a physical world seems unrealistic, however, Heinlein uses one fact to his advantage that appears to be undeniable. We are all “alone” in a sense in the world. Throughout life all of our knowledge is gained through two ways: what we are told by others and what we observe for ourselves. What we are told by others is not always reliable (if it is ever, assuming that the world in Heinlein’s story is reality), and if you think about it, we only truly know what we have personally experienced. So, if it turns out that everything we have been told throughout our lives is a lie, then our entire reality would be completely different, other than the observations made by ourselves personally.
We all accept whatever reality we live in, so if in reality we are being lied to, we would be powerless in finding the truth. I can only speak from the perspective of a teenage boy, so I can say that I have never died or had many other experiences. Since we only have other people to rely on to inform us on what we do not know, then those experiences could in fact be completely different that we had thought, if they existed at all in the first place or were just “performed” for the sake of the one person who is trapped in Heinlein’s world. One that Heinlein brought up was death. Since I can say that no one has ever died (and can still talk about it) we, as individuals do not definitely know anything about it. For all we know, death itself could be completely non-existent, and the other “fake” people around I the world are not truly dieing, but just “acting” in order to create a false sense of purpose for the trapped man. Since we have never experienced death, we cannot say that we will ever die. It seems that in the end of the story, the world is being “reorganized” as if the man is being placed into a new reality to relive his life now that he has discovered the true reality around him.
If we can never die, then it brings up questions about humanity. If we do not know that humans are immortal, then there could be other things about humanity that we do not know. There are endless possibilities about what we can do as humans and it could only be a matter of recognizing these abilities before truly being able to utilize them (like Neo in the Matrix, who only had to realize that he had the power to alter the matrix before he could actually do so).
Also, if the world we live in is a lie, then how do we know that it is even physically what we believed it to be? Personally, I have never been outside of the United States (not that I can remember, at least), so there is a chance that the entire world that I believed existed is all made up, like it’s history. My life could theoretically exist of nothing more than a few states with false stories of things occurring in lands that “exist” only to create a more believable and complex world and take the focus off of the true nature of “reality”. Basically the world around us is reality as far as we can tell. We can have speculations such as the ones that this story brings up, but so long as we stay oblivious to what reality truly is then it could be argued that what we perceive to be reality is reality. Since the only ones who can perceive the world is ourselves ("i think therefore I am". We don't know if anyone else is "real" in the sense that they have a "spirit"), what we know is reality. As I said at the beginning of the essay, the only thing we can accept as reality is what we can perceive, so our world is everything we can perceive it as. If we never come into contact with anything that would suggest that reality is not exactly as we think it is then for all we know reality is exactly whatever we want it to be. This is just like Cutie, who, though he lived in a world where he was created to serve humans, believed whole-heartedly that he was the highest life form whose roll was to serve “the master”. Unable to perceive anything other than what he knew, Cutie was living in a world where he served “the master” as far as he knew.