Actually if you think about it even if you were to consider Witchcraft simply a science then it would still be a religion as well. The reasoning behind this is that religions have dogma (rules) by which to practice, work and worship. Simply from a scientific point of view all sciences have a prescribed set of actions which are to cause an effect or change in some way. These rules of practice and performance are much like dogmatic rules in a way. Everything could be the higher power to which you give honor or thanks and recognition. Whether it be the science itself, the elements used therein or the outcome or other outside force. All people have a God of one form or another, whether it be themselves, the universe, a tree, a concept, money etc. All things could be considered religious in nature. It all has to do with the perception of the person involved. Whether divine or secular.