From the introduction:
Foolish indeed are they who laugh at what they do not understand. The ancient and remarkable practice of divination was once universally venerated. I do not trouble myself much with fleeting thought and fashion, but it seems the study of this school of magic had fallen out of favor amongst mortal wizards until recently. This reflects poorly upon mortals, in my opinion.
I care little about the promotion of one school against another and feel no compulsion whatsoever to defend my own particular studies. However, at the request of an old friend to whom I owe a debt, I have put together this guide for students of divination. It is necessarily brief as my other duties are very demanding, and also because I can muster only a small amount of interest in the task.
Those reading this work should not trouble themselves by offering praise or criticism—I care nothing for either.