It's amazing how many people think that something called the "Three-legged Stool" is Anglican. Actually, it is contrary to true Anglicanism. I wrote a paper about it back in seminary, which is included here. The punch-line, if you don't want to read the entire thing, is that an author from 400 years ago has been misquoted, and that misquote has been further twisted and misused over time. Richard Hooker lived around 1600 AD, and he wrote about some of our most significant Anglican theology. Included is a paragraph where he refers to the sources of authority. He says clearly that Scripture is foremost, and stands alone as divinely inspired. He says that in order to grasp the meaning of Scripture, God has given humans the faculty of spiritual discernment. Over time, the universal church also exercises such discernment corporately, and provides insight for future generations. These three elements all figure-in to discovering God's Truth. However, the metaphor of a "Three-Legged Stool" gives the impression that these three are of equal weight. This is not what Hooker taught. Read more about it below....
http://dl.dropbox.com/u/10238178/REASON.pdf