It would help a lot in understanding Dostoyevsky to learn about Eastern Orthodox Christianity. You cannot, I stress,
cannot separate Dostoyevsky from his deeply Orthodox sense of Christian morality and spirituality. Yes, people--especially non-Russians--do it all the time. But you're not going to grasp Dostoyevsky is any genuine sense unles you contend with his spirituality. He was an Eastern Orthodox Christian and he wrote as one.
In the Christian spiritual tradition, there is what is called a "Holy Fool" or "Fool for Christ." It's a spiritual
archtype--a spiritual ideal--not necessarily a portrait of any real person. Historical persons labelled Holy Fools have often been mentally handicapped, mentally ill, people consciously acting against social convention despite the consequences, or perhaps in a few a cases, people who would be now dx'd with a developmental condition.
In Russia, a Holy Fool is called a yurodivy, and it is well-known that
yurodviy characters appear in a few of Dostoyevsky's works, including
The Idiot. We can back up these interpretations, in most cases, by the many notes Dostoyevsky left su in his hand-written manuscripts. Reading those notes are very illuminating into how Dostoyevsky wrote intentionally as a Christian writer, very concerned with spiritual and moral imagery and symbolism.
So if you're suggesting Prince Myshkin is suppose to be an Aspie, I would have to say that's reading into the text. That wasn't the author's intention. His intention was that the prince would be a Holy Fool, a Christian spiritual archtype and moral symbol. You can make analogy between Prince Myshkin and Aspies all you wish, but to say the prince was an Aspie, or on the spectrum, would be a faulty interpretation and disrespectful of the author's intentions.
This is a very good post and extremely to the point. I'm not Russian, but I have extensively studied Dostoevsky and Mercurial's interpretation is in line with Dostoevsky's journal and other similar sources.