Q: Isn’t the mental age of the reincarnators too low?

D「It is hard to say anything definite with regards to this. I can think of several causes, but only at the level of a hypothesis.」
M「It is unlike you to be vague.」
D「It is not like I know everything of course. If anything, I actually strive not to know. If you know too much then things become boring, right?」
M「Is that how it is then?」
D「That is how it is. Now then, I believe the reason why the mental age of the reincarnators feels low is probably because they are being affected by their physical bodies and by their environment.」
M「For their physical bodies I can somewhat understand it, but what about the environment?」
D「Indeed. For the reincarnators, particularly the ones pent up in the elf village, like birds in a cage, they were living a life without any change after all. Change is an important factor for people to mature. Without anything new occuring people stagnate, and stagnation basically inhibits people maturing into adults. In Japan, people go to kindergarten, then they go to primary school, then they go to middle school, then high school and university, then finally emerge as full members of society, with their position changing as their physical bodies grow. I consider this change to be an important factor for people to mature. When change occurs people work hard to match that change and they also take lessons from it. However, if a life without change carries on and on, then they cannot grow. Especially for the reincarnators who were pent up in the elf village with others that they knew from their past lives, as that relationship provided no stimulus. It would not be a surprise for them to treat their new lives like an extension of their previous high school lives and stagnate like that. And that is how my pet theory goes.」
M「Whether they did or not, it has a certain persuasive power indeed.」
D「Afterwards, it will be a matter of whether or not they put in any effort to truly mature. If people do not consciously put in any effort to mature, they stay surprisingly childish. It is not like children simply turn into adults after a certain amount of time. If children are in an environment where they cannot mature or where they are unable to have the desire to mature, then they will stay children no matter how much time passes. You could also say that they are unable to forget their childlike innocence. Even grown adults can stay childish on the inside without maturing. They have no desire to mature. They do not even have the awareness that they have not matured. So perhaps the reincarnators were unable to mature due to their environment. You could also consider it being a situation where due to their environment their intention to mature was blocked.」
M「How unusual for you to be seriously discussing theories of education!?」
D「How rude. I am always completely serious, okay?」
M「Eh?」
D「Eh?」