Campbell argues that though the educated are often the first to articulate a new cultural perspective, if that perspective becomes popular, it will spread across the population. As a result, the education levels associated with that perspective naturally average out. So it is that the relationship between intelligence or education and cultural shifts may not be as significant as they first appear.
To me, this is not at all surprising. For years I have watched religiosity being connected with ignorance, even while some of the most intelligent and educated people I know are (slightly) religious. To me, the missing link in this debate is fashion.
Half a century ago in Ireland, Catholicism was all the rage. Non-Catholics, particularly atheists, were outsiders, minorities - people to be frowned upon and ostracised.
Between then and now, Catholicism collapsed, so that by the time I was growing up in the early 1990s, outward signs of religiosity were deeply uncool. No teenager in their right minds would openly pray or bless themselves in my school - because the mob had switched sides and now the religious were the targets. The people most likely to admit respect for religion, and risk the contempt of their peers, tended to be the most academic students.
It was all a bit baffling at the time to hear people talking about the power of the Church while it appeared to be in terminal collapse. The mob, which 50 years earlier was silencing critics of Catholicism, were now gearing up to silence its defenders.
When conservative Catholicism really was powerful, those who opposed it were brave indeed. As Campbell suggests, they may have been the more educated people back then - quite a few of Ireland's poets and writers took pride in irritating the Catholic hierarchy for example - but over time their message spread to everyone else too.
By the 1990s irreligiosity was so common that its adherants were no longer an educated elite who had abandoned religion after a thoughtful, rational inner debate. Instead, irreligiosity became a growing assumption, a non-issue. The altar was replaced by the advertisement, unthinking allegiance switched from priest to public relations. It was not a new Enlightened Ireland, but rather a fuzzy mixture of consumerism and the profitable modern superstition of Irish Psychics Live. Catholicism was uncool, and theism unconsidered.
The people who defend religious conservatism in Ireland today are the ones taking a risk, willing to face public displeasure. It seems unsurprising that some have quite high levels of education, enough to cause them to question the growing consumerist, anti-Catholic consensus - the new religion of modernity.