As with many other things in life, Magick has certain fundamental laws or tenets. These laws should be given careful thought, since they provide insight into the inner workings of magick. Also, they will help ensure that you get results and avoid mistakes. This list is not exhaustive, and does not include some of the more universal laws (such as the Three-Fold Law), but these are some of the more important ones.
The Law of Contagion states that any thing that was a part of an entity retains an association with that entity, or has relevance to it. Your fingernail cuttings, for example, were once part of you and therefore have an association with you. They could be used, quite successfully, to work magick on you should someone so desire. This law also holds for objects that have been in close contact, over a period of time, with a person or thing – such as rings, articles of clothing, and so forth. These things contain the energy of the owner or wearer, and thus form a link
The Law of Similarity is a law frequently operating in conjunction with the Law of Contagion. This Law of Similarity states that things that look like each other can be thought of as alike. For example, if you were doing a spell for the health of a friend's cat, you might use a candle in the shape of a cat, or a picture of the cat, to represent your friend’s animal. This is a type of magick known as sympathetic magick and is quite effective. Also, it works in conjunction with the Law of Names in that if you 'name' an object with a particular name (the name of the cat in our example), the object is what it has been named for.
The Law of Names is behind the old belief that ‘if I know your true name, I have power over you'. It is similar to the Law of Contagion, in that an entity's name is an integral part of that entity. Knowing a thing’s true name gives you a key to its nature. Many Wiccans, for example, have up to three names: a Witch name that they share with no one else, a coven name known only to their fellow coveners, and finally, their mundane or public name. In your workings, it is always more effective if you can use a name in your spells.
The Law of Personification means that anything that can be conceptualized can be personified. This law is the principle behind, for example, popular figures from myth that take on a life of their own (and subsequently can be invoked in rituals). Over the course of time, so many people think about the character that it becomes personified and is almost an entity on its own. Many Pagans know of Squat, the "God" of finding a parking space. He has been invoked so much that he has taken on a life of his own and will indeed readily help when called*. There is also the example, cited by Elizabeth St. George in her book Casebook of a Working Occultist, in which she successfully invoked Star Trek's Mr. Spock to help with a serious problem during the Apollo 13 space mission.
The Law of Balance and Complement is sometimes taken as two separate laws. Usually, though, they are taken as one law. The Universe constantly tries to balance itself and achieve equilibrium; light seeks the dark, dark seeks the light, opposites attract, and so forth. Therefore, energy sent out will ultimately return to you, in order to achieve that balance.
The second part of the Law (also known as the Law of Polarity) states that everything in the Universe has its opposite or polar complement. Each contains the seed of the other as an intrinsic part. Without these, there could be no balance in the Universe – no day without night, for example. Viewed in this light, the concepts of ‘good' and ‘evil', ‘male' and ‘female', and other such pairs take on new meaning, since neither could exist without the other. The familiar yin-yang symbol is a visual representation of Law of Balance and Complement.
SOURCES
Farrar, Janet and Stewart. The Witches' Way. Blaine, Washington: Phoenix Publishing, 1986.
Leek, Sybil. The Complete Art of Witchcraft. New York: Signet Books, 1971.
Bonewits, Philip Isaac, Real Magic. New York: Samuel Weiser, Inc., 1991.
St. George, Elisabeth, Casebook of a Working Occultist. London: Rigel Press, 1972.
Conversations with students in my Wicca 101 classes
*When driving around, desperately seeking a parking space where there is none, one invokes Squat thus: Squat, Squat, find me a spot. Spare me from having to scout! Squat will listen and find you a spot. It sounds funny, or weird, but it works far too often to be very laughable.