Let’s imagine a 2D world with only x and y axes, where the inhabitants have no knowledge of the third dimension — they are unaware of what exists above and below their plane. In this world, you arrive and position yourself so that your z-coordinate never reaches zero, effectively existing in a dimension perpendicular to theirs (their plane is z=0). Since you don’t touch their plane, they cannot perceive you, but you can observe them, and nothing is hidden from your perspective, including what may be concealed from every direction within their dimension. Now, suppose you speak, causing confusion among the inhabitants as they wonder where this voice is coming from, a concept entirely foreign to them. Does this mean they will never be able to comprehend your existence through their intelligence, prompting them to cease their inquiries about the source of the voice?

The answer is no; they can indeed deduce the source of the voice. At the very least by their intelligence, they can come to realize that their knowledge is incomplete. If you so choose, you can elevate one of them into the third dimension, instantly granting them an understanding of the broader reality.