This photo meets the challenge very well. The shadows play an intricate part in the photo.
The shadows don't seem to go with the subject. By that I mean I don't see a connection between the subject and the shadow. That is not necessarily a bad thing, it just makes it a bit unsettled for me.
In you comments you say these are leaves. For me, I would no have known that. It looked to me like some sort of vegetable. I see now that they are leaves.
The composition is good. The eye moves nicely across the photo.
I do like the contrast of the color of the leaves against the monochrome background.
I hope this helps.
Feel free to contact me if you have any questions.
Sometimes I think Zen may actually be an exercise in ascribing profundity to things that in fact have absolutely no significance at all. Like this. Is it deeply meaningful? Or is it just simplistic BS? Are the colours important? Are the shapes? It certainly feels satisfyingly heiroglyphic! Plus there's the tantalising fact that these leaves are kin to those that cast the shadows. All things considered I don't think this image means anything at all, but it does ask me a lot of questions, and that's far more than 99% of the images here can manage. So that must be true Zen, yes? 7.
I'm not sure there's enough sense of peaceful composition here to really njustify your title; the shadows are rather hectic, and actually the blalnce of the positioning of the two leaves or whatever is slightly uncomfortably - quite apart from the zen idea of the manipulation of materials being outside my understanding of the groove. There is, however, a certain feel of lightness to it - down to your exemplary capture of a sense of brightness without blasting the highlights - which fits your title.