Modernism, as condemned by Pius X, was a rather vague description of the philosophical underpinnings of a movement around the end of the 19th and beginning fo the 20th century. Two of the more prominent Catholics condemned for Modernism were a French priest, Alfred Loisy (1857 - 1940, excommunicated 1908) and George Tyrell , and Irish Jesuit priest (1861 - 1909; expelled from the Jesuits 1906 and suspended for sacraments or excommunicated 1907).
Much of it philosophically was based on the work of various philosophers, including Hegel, Nietzsche, Kant and Schopenhauer, and is driven by rationalism, positivism and materialism.
It looks at the Church and dogma as mere human institutions which may be radically changed over time. It took a rationalist approach to the Bibile and interpretation of it, and was skeptical of or denied miracles and the historicity of narratives.
It held that dogmas could evolve over time - in other words, change radically; this is different from Cardinal Neumanâs approach which said that doctrine could develope over time in that what was inherent in the Gospel would become more fully explicated.
Modernism in biblical scholarship attempted to evaluate the text alone and ignored the Fathers of the Church, and as such was a thinly veiled form of sola scriptura.
The term Modernism was dropped, about the time of Paul 6th, in favor of terms that were less vague and more oriented to the specific problems, such as secualrism, liberalism, and relativism.
The use of the term âmodernismâ is popular among some critics of things they do not like in the Church, and too often is nothing more than yelling âboogeymanâ as it is applied not to a dogmatic issue or a scriptural approach but rather to a disciplinary issue that has nothing whatsoever to do with dogma or scripture. In short, the thinking seems to be âThat (idea, action, decision) is something I donât like and I donât understand the thinking behind it, but I donât like it and I donât think if jibes with my view of what the Church should (think or do), so it is just Modernismâ.