What is the difference between the curve of Wilson and the Monson curve?

curve of Wilson goes from lateral end of tooth from one side to the other end of the other tooth on the other end of the same arch. it is like from the lateral end of right 1st moral on max arch to the lateral end of the left 1st molar on the same arch. The SPHERE of monson (imaginary) is basically a combination of Wilson curve with curve of spee (curve of spee: goes from anterior teeth to posterior passing through the occlusal sulcus).