Philosophers continued the fragmentation. Descartes inverted the medieval approach to knowledge, putting the Self as the reference point for knowledge. The Enlightenment was "an attempt . . . to find a common basis outside religion for determining moral truth.".
It was a decisive break with the Christian legacy of the West. Deism now became the forming theology. Spiritual and secular are to be separate realms.
This worked while many people were still Christian or church- goers. Enlightenment morality depended on the virtue of a moral and religious people. There was still "a strong shared idea of the Good and a shared definition of virtue."
The swing of the pendulum came in the romantic movement's exaltation of emotion, freedom and individualism. This was a reaction against rationalism but not a return to faith.
Atheism in the 19 th century was real but kept in check by vigorous revivals and religious fervour. The secular elites pursued a secular revolution that introduced reformist and essentially secular thinking into established institutions. The early 20th century pushed religion further to the edges of life.
I can't help feeling that the world wide traumas of Wars and economic chaos in the 20th century worked to delay the unravelling of Western values. People held on to traditions in the face of barbarism and suffering. But post war Western society saw further unravelling of the Western tradition. Dreher relies on Philip Rieff's analysis of the advent of Psychological Man in the 60's and Charles Taylor's insights. The triumph of Eros marks our time. Desire expressed as the assertion of individuality is the underlying world view. Thus same-sex marriage is asserted on the basis of love and desire, disconnected with any relation to biological embodiment. Dreher notes: "The Romantic ideal of the self-created man finds its fulfilment in the newest vanguards of the Sexual Revolution, transgendered people. They refuse to be bound by biology and have behind them an elite movement teaching new generations that gender is whatever the choosing individual wants it to be. . . Transgenderism is the logical next step, after which will come the deconstruction of any obstructions, in law or custom, to freely chosen polygamous arrangements."
This new concept of liberty is the right to define one's own concept of existence, of meaning, of the universe, and of the mystery of human life (citing a US Supreme Court Justice).
So the West loosened its grasp on God as Creator and Lord, and now has arrived at a unravelling of human bonds with our bodies. The autonomous Self rules now, a god its own right. There is no ordered creation to which our desires must submit. Dreher: "The West has lost the golden thread that binds us to God, Creation, and each other. . . . We have been loosed, but we do not know how to bind."
So how does the Christian church, carrier of a very different world-view, respond, even to preserve itself in this corrosive sea that seeps into us? " We who still hold the golden thread lossely in our hands must seize it more tightly and cling to it for future generations, or it will be torn from our grasp."