You are right. I was just trying to come up with a generic term for 'the physical world'. Neurons are made up of molecules, Neurotransmitters are molecules, a 'chemical'. Even the spark of the brain, isn't it just calcium ions carrying the charge.

Guess I was just off-hand thinking that 'chemicals' was 'reasonable' cutoff point from going too small, but small enough. It was off the cuff scaling, I have no real evidence where we would stop on the sliding scale from larger emergent properties.

People that go smaller, to quarks, and throw in Quantum Mechanics are usually not super serious. It gets woo-woo.