If a Catholic cannot name at least one article of faith that he believes principally on the basis of the authoritative teaching of the Magisterium, he’s either a saint or a Protestant.
I have read this statement a couple of times now on the Internet, and apparently it might have its origins in Fr. Al Kimel. I have to say that I am not at all comfortable with the statement, primarily because authority is not created to impose, but rather define. But how does it know what to define?
When the Fathers of the Nicene Council got together to write the Creed, it was NOT a legal act. It was an act of witness to the life of the Church. The life of the Church expressed the fact that Jesus Christ is both fully God and fully man. It was the spontaneous sense of the Faith that makes the Nicene Creed true, not a legal definition.
Therefore, I would like to think that all of our dogmas, even the ones that are most disputed, have their heart and source in the life of the Church itself. If they do not, what is the point? As I like to say, if you cannot express the sublime mystery of the Trinity starting with a blade of grass, you don't know theology. (And that is why I am no theologian.) I would like to think the same could be said of purgatory, the merits of the saints, etc.
Nevertheless, I suppose that as a layman, I defer to those who are appointed to determine these things. In what is important I think we are all certain. These finer points have little to do with the Holy Ghost's presence in the world through our Christian lives.