You take a stone
You drop it
It fell down

Why?

Gravity
Matter tells space how to bend
Space tells matter how to move

I accept it

A live wire
You touch it
You got shocked

Why?

Flow of electrons
Similar flow is in your nerves
The external flow disturbing your nerves

I accept it

You are sick
Vomiting
Your head hurts

You take some medicine
Time passes
Now you are fine

Why?

Chemical reactions in your body
I'm not sure
I'm not a physician

But...