Great article

I found a great article on energy in the Imbolc '06 issue of "Cauldrons and Broomsticks".

..."One particular definition of energy might be “Energy is a fundamental quantity that every physical system possesses; it allows us to predict how much work the system could be made to do, or how much heat it can produce or absorb. In the past, energy was discussed in terms of easily observable effects it has on the properties of objects or changes in state of various systems. Basically, if something changes, some sort of energy was involved in that change”. In my opinion, so far as magick is concerned, the most important part of that statement is: if something changes, some sort of energy was involved in that change.
This does gives us something of a clue about the nature of energy. It cannot be created as it is something which already exists by virtue of the fact that “every physical system possess [it]”. It cannot be destroyed, only converted into a different form. For example, the wheel of a bike spins by virtue of its energy. To stop the wheel spinning, that energy is converted to heat by the brakes.
And so to magick. The energy we use already exists, both within us and without us. After any ritual or magickal operation, we can either be left feeling pretty much ok; bursting with energy as a result of not using all of the energy we have drawn into ourselves; or exhausted. The exhaustion comes about as a result of using our own energy rather than drawing any in from 'outside' and so leads to our reserves becoming depleted. The exhaustion will normally continue until we replace that energy by resting or from eating. But where does the outside energy come from and how do we draw it into ourselves? "...