Inertia
http://scienceworld.wolfram.com/physics/Inertia.html

Weight
http://scienceworld.wolfram.com/physics/Weight.html

Mass
http://scienceworld.wolfram.com/physics/Mass.html


"The time has come," the Walrus said, "To talk of many things:
Of shoes, and ships, and sealing wax, of cabbages and kings.
And why the sea is boiling hot and whether pigs have wings."

Makes about as much sense as Shead eternal struggle with inertia,
weight and mass.