Ratzinger on Gaudium et Spes

If it is desirable to offer a diagnosis of the text (Gaudium et Spes) as a whole, we might say that (in conjunction with the texts on religious liberty, and world religions) it is a revision of the Syllabus of Pius IX, a kind of countersyllabus ... Let us be content to say here that the text serves as a countersyllabus and, as such, represents on the part of the Church, an attempt at an official reconciliation with the new era inaugurated in 1789. … the one-sidedness of the position adopted by the Church under Pius IX and Pius X in response to the situation created by the new phase of history inaugurated by the French Revolution was, to a large extent, corrected via facti, especially in Central Europe, but there was still no basic statement of the relationship that should exist between the Church and the world that had come into existence after 1789. In fact, an attitude that was largely pre-revolutionary continued to exist in countries with strong Catholic majorities. Hardly anyone will deny today that the Spanish and Italian Concordat strove to preserve too much of a view of the world that no longer corresponded to the facts. Hardly anyone will deny today that, in the field of education and with respect to the historico-critical method in modern science, anachronisms existed that corresponded closely to this adherence to an obsolete Church-state relationship.

 Cardinal Joseph Ratzinger, Principles of Catholic Theology, pp. 381-382.