Conservation of Energy and The Nature of Forces

Today I have been toying with a bunch of things:

1) Conservation of energy, I have been writing this section for the book project. Nice approach, if I do say so myself. Did you know that we really don't know what energy is other than a calculated number that remains the same in a closed system? We have no better understanding of energy than that. Despite being able to calculate it, predict it, and use it in other kinds of calculations; we have no idea what energy IS!

2) In Newtonian mechanics the entire game is chasing the forces. We have F=ma, and people think this is the definition of force. No! This states that the numerical quantity of force is equal to the product of mass and acceleration. If you do not know what F is prior to doing a calculation you will not be likely to figure it out.

3) I have been messing around, playing with trigonometric and hyperbolic functions.

Been having a lot of fun with these things.