I thought it was the Law Of Gravity.
The law of gravity is simply the observation that if you drop something, it will hit the ground. It doesn't explain why that happens, nor does it explain how that happens, nor does it predict the gravitational pull two objects will exert upon each other. That things tend to fall is the Law -- everything else is gravitational Theory. And say what you want about gravitational Theory, it sure ain't bunk.
Cut the Gordian knot. Google law of gravity and theory of gravity as phrases. See which gets the most hits...