of course ther is a reason to why it is the way it is - it lies in the Hexachord (mostly) and in the way peeps used to think, work and live back then. i will post on this topic as soon as Walter Haberl (friend of mine) is done with his book on this ancient topic (he rediscovered all of it).
Other than that you can find a lil explaination on notes and tunings in my Host section:
http://www.guitartricks.com/2000/trick.php?trick_id=5648
[FONT=Times New Roman]Holiness is in right action and courage on behalf of those who cannot defend themselves. What you decide to do every day makes you a good person... or not.[/FONT][br][br]