We typically think of our western culture as being secular.
Western civilisation was not born out of secular (non-religious) concepts. Great Britain was a Christian nation when it colonised a large part of the world and Christian concepts formed the basis of its government, education and laws.
America similarly had a Christian worldview underlying its formation. The Mayflower Compact was the first document written by the early western settlers of America when they landed at Plymouth Colony. In it the Pilgrims write (emphasis mine):
Having undertaken, for the glory of God, and advancement of the Christian faith, and honor of our King and Country, a voyage to plant the first colony in the northern parts of Virginia, do by these presents solemnly and mutually, in the presence of God, and one of another, covenant and combine our selves together into a civil body politic…
But during the enlightenment in the 1800s ideas were born that began to remove spirituality as part of the widely accepted worldview. Rationalistic concepts began to take hold of culture until in 1882 Nietzsche famously wrote that “God is dead”. This naturalistic worldview that views science as the only source of truth provides a way for people to write off the existence of a God and that seems to be what people have done.
Census and statistical data from Australia, America and the UK all show a decline in ‘religious’ people which demonstrates the impact this naturalistic worldview has had. 
However, this secular age didn’t last long as people have sought to fill the spiritual gap in their lives through other forms of spirituality. This spirituality is not ‘religious’ but instead is described as ‘spiritual but not religious’.
People associating with this term has been rising with Barna research reporting almost 10% of Americans forming part of this group.  This 10% does not include those who associate with a religion but whose spirituality has become a much more private affair not associated with corporate, organised worship.
A PRRI study adds another 10% when including those who see themselves as connected to an organised religion but would be classed as ‘spiritual but not religious’, putting the total at 20% for America (3).
Statistics for other nations are harder to come by as this group doesn’t fit the typical options of Christian, Muslim or not-religious, etc.
Peter Jones, a pastor, author and scholar says that this shift away from pure rationalism towards a religionless spirituality is due, in a large way, to the work of Carl Jung. For many years Jones has seen and spoken of the shift in western culture away from Christianity and towards a pagan concept of spirituality that encompasses all the new-age spirituality that we are seeing rise up before our very eyes.
In his book, “The Other Worldview”, Jones describes how this Jungian rationalist-cross-spiritual worldview has been the driving force behind many of the cultural changes we have seen recently from same-sex-marriage to the plethora of genders to the lack of guilt over what used to be clearly guilt-worthy issues of abortion and euthanasia.
The basis of Western civilisation (if I can still call it that) is no longer Christian concepts. But it isn’t science-based rationalism either. We have moved all the way through a rationalistic scientific worldview and onto a pagan spirituality.
Peter Jones is speaking about ‘The Arrival of the Post-Secular Age’ at Reformers Bookshop on Monday the 21st of October. Click here for more details.