According to that logic, a tailless aircraft couldn’t be either nose heavy or tail heavy.

However, pitch stability is not determined by the location of the stab respect to the main wing.

The more or less authority of the stab, wherever it is, comes from how much the airstream helps it or not to stabilize the main wing.

In conventional, layouts the stab works against the lift produced by the wing.
In canard layouts, the stab helps the main wing to lift the aircraft, and then a smaller wing is possible.

This website has animated pictures with very clear explanations.

http://www.geistware.com/rcmodeling/...rorgravity.htm

Just click on the tabs under each picture to activate the animation.