>Insight: How could we, if we can, use Yuyuko to determine this Gensokyo's authenticity?
>This really determines what the nature of the problem is. You and Yuyuko has known each other for a long time, and there are quite a few old memories and secrets between the two of you. If someone were trying to create a false Gensokyo around you, then they would be quite hard-pressed to know, say, the first meal the two of you shared in the netherworld or what Yuyuko did the last time the two of you watched the sunrise together from the eastern-most tower. You have encountered such illusions in the past, there have been fox youkai who are quite good at crafting such things. If you are able to establish that this was happening, the question becomes how to break the illusion. With sufficient will, one can ignore or dispel them, but this requires one ignoring the evidence their senses give them, which can be difficult if one hasn't found enough reason to doubt them.
>However, things become more complicated if the illusion isn't created by someone, but rather the product of your own imagination such as a dream or hallucination. At that point, you suspect she would know anything that you would expect her to know. It would then become a question of how to defy your own expectations, doing something or getting her to do something that exceeds what you would ever anticipate and see what happens. Possibly you would have to find a way to challenge yourself with something you have no way of knowing, and see if the gaps could be filled in in a reasonably coherent manner. With regards to Yuyuko, you would have to be very creative: you know her quite well and she knows you very well. If it is some sort of hallucination, you would have find a way to make it stop. A dream, in theory, you would need some way to wake up from.
>It is possible that you may be dealing with a combination of both, someone is using your mind to create falsehoods around you, and then using their own knowledge to fill in the what you cannot. If this were the case, then things become difficult indeed. You would have to find some way to trick this person into making a mistake, and that means you would have to find a way to have them read your mind incorrectly. You aren't sure if that would be possible. While mind-reading magic can be misdirected with sufficient effort, things such as satori are notoriously impossible to deliberately fool. Using Yuyuko to establish this would not be easy, it would take a creative combination of lies and misdirection until such a time that you can find mistakes enough to show that something is wrong. You are not certain if using someone you know well or someone you hardly know would be better for such an act. And if it were the case, you would have a difficult time overcoming it, you would need to find who or what is doing it and then stop them without them weaving more illusions around themself to stop you.
>_
