Does Buddhism view mind phenomena as chemical or as supernatural? I was once again challenged by my scientific friends: who say that all mind phenomena is just chemical reaction!

My question is, how does Buddhist philosophy view this question? I'm leaning towards my science friends' view, after reading A Manual of the Excellent Man, where the seven aspects of perception on materiality are considered to be the combination of natural elements.

If so how does a chemical overpower another, and is the transcendental self also chemical / elements? Because if it were not, then we could assume spiritual forces were active in creation, etc.!
Consciousness (viññana) and Materiality (rūpa) are related as are magnetism and electricity. Their relationship is reciprocal, each conditioning the other. They are dependently originated, i.e. neither exists independently.