De Ratione Magi Vitæ
Study Logic, which is the Code of the Laws of Thought. Study the Method of Science, which is the Application of Logic to the Facts of the Universe. Think not that thou canst ever abrogate these Laws, for though they be Limitations, they are the rules of thy Game which thou dost play. For in thy Trances though thou becomest That which is not subject to those Laws, they are still final in respect of these Things which thou hast set them to govern. Nay, o my Son, I like not this Word, govern, for a Law is but a Statement of the nature of the Thing to which it applieth. Nor nothing is compelled save only by Nature of its own true Will. So therefore human Law is a Statement of the Will and of the Nature of Man, or else it is a Falsity contrary thereunto, and becometh null and of no Effect.
 On Reason in the Life of the Magician