The problem lies in our narrowed view of logic. First, examine things which do not fall. Clouds, for example. By the cloud's example we see that gravity is not all it's cracked up to be. Neither is the ground.
Earthquakes can occur when the ground becomes cracked.
By this mechanism the ground can separate from itself. Therefore we must insist that the Earth can leave the ground. Now, consider a common ping-pong ball, bouncing on the ground during an earthquake. The ball will weigh 2.5 grams. This fact may become important later on.