This rainbow appeared over my town today.
Rainbows are used in our tradition as an example of how something can appear vividly to us and yet also not exist in the way they appear. Rainbows appear to be in a certain location, a certain distance away. But we know that if we go to the place where the rainbow appears to be (even if we run) we will not be able to find it.
We know rainbows don’t exist in the way they appear to exist, and because of our familiarity, we miss the important significance of them. The significance is that all phenomena exist in a way that is different from how they appear to exist. We can use the example of the rainbow to start us thinking in the right direction.