Everything in the universe vibrates. All matter, all energy - even your life itself - is a vibratory activity that conforms to precise natural laws. If you want to understand why the universe is the way it is, you must understand how vibrations operate and manifest. You will get you on your way.In You, the follow-up work to Master Key System, Charles F. Haanel explores a range of subjects from astronomy to astrology, from physics to alchemy, and much more.Matter in motion and ether under strain constitute the fundamental principles with which we have to do in physics. These are both vibratory activities. We speak of them as if there were two principles; there is, however, but one principle with a dual manifestation: it is cause and effect. Matter in motion puts ether under strain, ether under strain puts matter into motion. All phenomena in the Universe are the result of the operation of this basic principle. Let us check up on those with which we are most familiar.