Richard Harrison wrote:

Cecil, W5DXP wrote:
"On the moon, a stone would be just as hard to throw horizontally, but
it would be easier to lift."

The normal forces are different on the earth and moon. But, the physics
book statement follows from Newton: F= MA, and M is the same on earth or
moon.

I think the point is that the inertia is the same, independent of what
the gravity might happen to be, thus demonstrating the most fundamental
property and defining feature of mass.

73, Jim AC6XG