You may have heard it said, as I often have heard, that Catholicism tends to be more "both/and" than "either/or." What does that mean?
I believe it means this: most errors (which is to say, most heresies) come about by emphasizing one truth to the exclusion of another truth. For example, we believe that both faith and works play a part in our salvation. If you emphasize works to the exclusion of faith, you have Pelagianism. If you emphasize faith to the exclusion of works you have Lutheranism.
We believe that both the Sacred Scriptures and the Sacred Traditions of the Church contain revealed truths of the Deposit of Faith. If you emphasize the Scriptures to the exclusion of Tradition, you have Protestantism.
I've just described the twin errors of Sola Fide (faith alone) and Sola Scriptura (scripture alone). Very little in Catholicism can be described as "X alone." We do, of course, believe in Sola Christe, which is to say Christ alone is the Way, the Truth and the Life. It is by Christ alone that we can be saved.
However, even then there is the danger of creating an "either/or" error. What about the Church? What about Mary? What about the saints? To emphasize Christ in such a way that excludes the Church and the saints is fallacy. It would be like claiming Shakespeare to be the greatest writer of the English language while simultaneously denouncing his sonnets and his great plays. One cannot revere the artist while denouncing the art.