"Oh, really!", Adrien exclaimed. "Then we're doing Air next?".

"Or Earth", Val said. "Whichever you want to do first".

"Then let's do Air", Adrien grinned in excitement. "I'm kinda prepared on that one!".

"Oh, you are?", Val said with a little smile and a tilt of his head. "Tell me everything".

Adrien set down his slice of bread on the plate, cleared his throat, and puffed his chest a little. "...Compared to Fire and Water, Air and Earth are more abstract... but still not as abstract as Light and Darkness. They're kind of in between, which makes sense, since, where they meet, they form the horizon. Right?".

"Yes, and that is a beautiful way of expressing it", Val smiled. "Yes... Air and Earth have a tangible form, but an intangible presence. Their nature is that of mediators between the concrete and the abstract, as you just said".