Maybe it's like drawing. A child draws a picture. He hasn't learned the concept of perspective, so nothing is the right size or in the right place. The Prophets have this two-dimensional picture of our universe because they haven't been exposed to certain concepts yet.
Sisko shows up, and suddenly their whole perspective is different. He is essentially their vanishing point. The picture is still on a flat piece of paper; they still don't experience
linear time, but now they know how to manipulate their flat piece of paper to make it appear as if the drawing possesses 3-dimensional qualities.