" In the realm of blue air more than elsewhere, we feel that the world may be permeated by the most indeterminate reverie. This is when reverie really has depth. The blue sky opens up in depth beneath the dream. Then dreams are not limited to one-dimensional images. Paradoxically, the aerial dream soon has only a depth dimension… The world is then truly beyond the unsilvered mirror. There is an imaginary beyond, a pure beyond, open without a within. First there is nothing, then there is a deep nothing, then there is blue "

― Gaston Bachelard