There are many different ways to correct errors within the Church, and the Second Vatican Council sought to put the Church back on course with the "medicine of mercy."
This is how St. John XXIII explained the aims of Vatican II in his opening address on October 11, 1962.
Previous councils in the Church would often define truth by condemning errors, but the Second Vatican Council decided to define truth in the positive, rather than the negative.
Recalling the horror of the previous two World Wars, St. John XXIII explained his reasoning.
Vatican II turned out to be a very different council than previous ones, choosing a more "merciful" look at the world and its problems, seeking to hold-up the truth of the Gospel for all to see, that they may be drawn to Christ through truth, beauty and goodness.
