I came across this post about writing what is unreal but true, and it reminded me of a Waterjewel saying: "Some things are real but not true, and some things are true but not real." It's about the different between material things (which can be solid but wrong) and immaterial things (which can be honest but not manifest). If the body and soul don't match, the body is real but the soul is true.
So too, you can write things which are not manifest in this world, but are meaningful and valid.
Don't be distracted by solid things just because they are solid, and don't lose sight of the truth just because it is intangible. Truth is more important than reality.