Falling freely

Newton was not the first, as I said earlier. It was Ismaël Bullialdus, who concluded the force is proportional to the square of the distance inverted.

How much one learns from reading! Anyway, my speed must increase if I fall down, since acceleration is proportional to the force.

This is mechanics, a kind of enhanced geometry, where you put in "mass", "force" and "time". Its is formal, and no measurements are needed. That is my definition. It is pure thinking (others claim mechanics is "dirt, sweat and tears"). What Newton studied was "celestial mechanics" rather than "astrophysics". His stars were not glowings bodies in cosmos. but merely points in a coordinate system. The achievements depend on the point of view, I should say. My climbing down will be strictly mechanical.
My friend is stuck. We use nuts and friends in order not to destroy the routes for our fellow climbers, and also protecting the environment. I have been told some routes are crowded with pitons. Others resemble refuse dumps. There are some climbers who use motor drills for attaching the pitons. They are not calculating to be followed by others. "Après nous le déluge" as madame de Pompadour said.