This is the largely case for the Japanese Buddhism as well in sync with Chinese Taoism.

The fifth element is synonymous with "void" or "sky", ie "空".

For a slightly abstract and colorful philosophy of martial arts, you may enjoy Miyamoto Musashi's Book of Void. https://en.wikipedia.org/wiki/The_Book_of_Five_Rings

It is more related to Aether in its Sanskrit origins. "आकाश"

If you're willing to make a linguistic leap, you could argue that "nothingness" or "無" constitutes the essential foundation of modern Japanese philosophy or philosophical Buddhism. https://plato.stanford.edu/entries/kyoto-school/