What first attracted me to The Young Wizards Series wasn’t the magic system, though I have to admit it is pretty amazing, but the characters. In the first book, So You Want to Be a Wizard, Kit and Nita are two teenagers who took on a great deal of responsibility without quite realizing the consequences of doing so. They’re scared, unsure, tired of being bullied, and in way over their heads. Diane Duane does an amazing job capturing their personalities and what it’s like to be a teenager thrust into an overwhelming situation.
The magic system is pretty awesome and makes reading this book well worth it, even if you don't like the characters. Practitioners have to actually know what they’re doing, know the proper names and dimensions what they’re working with to affect any change. Because of this, the practitioner has to actually think about what they’re doing and why, because bad intentions can cause a spell to go awry. Magic isn’t treated like some game, because it isn’t. What a wizard does can have real world consequences. There was a lot of thought put into this system, from how it works, to why it works and I love when an author cares enough about their work to do that.
I also love the Wizard’s Oath:
In Life's name and for Life's sake, I assert that I will employ the Art which is its gift in Life's service alone, rejecting all other usages. I will guard growth and ease pain. I will fight to preserve what grows and lives well in its own way; and I will change no object or creature unless its growth and life, or that of the system of which it is part, are threatened. To these ends, in the practice of my Art, I will put aside fear for courage, and death for life, when it is right to do so -- till Universe's end.
and this section from the manual:
A wizard's business is to conserve energy -- to keep it from being wasted. On the simplest level this includes such unmagical - looking actions as ... and supporting the people around you in getting their lives to work.
I think that right there pretty much sums up why I love this book and series so much. Magic isn’t about gaining power or riches, it’s about helping others and having sympathy for those around you. This theme, while heavily emphasized throughout the series is really hammered home in the first book.