Politically and socially, secularization is the creation of institutions independent of ecclesiastical authority — the authority of churches and religious groups. In the past, religious figures held the authority to govern, deliver medical care, and educate; today, such responsibilities have been taken over by non-religious authority figures who deliver the services independent of church structures. Independence from the church, though, also means independence from superstition.
Secularization creates freedom from superstition not because religion and church are necessarily and inherently superstitious (though there are arguments to be made on behalf of that). The connection is much broader because superstitious thinking is magical thinking: it's the belief that there are magical, supernatural, or paranormal forces at work in the world which operate in violation of the natural laws that normally govern everything.
Religion & Access to Supernatural Powers
Traditionally, knowledge of and access to such forces have been controlled by religious figures and institutions. Priests and shamen, for example, have been sought out for faith healing or for prayers that would help someone in a financial matter. The average person might be able to invoke these forces on some levels, but never as effectively or powerfully as religious specialists.
Once the authority of religious figures and institutions is set aside, then, people need to find some other way to look at the world. Sometimes they will make up their own means for accessing the supernatural or the magical, but in many other cases they will have to set that aside as well in favor of more rationalized approaches — exactly the sorts of approaches which dominate rationalized, secular institutions. All of this, in turn, is created to be in principal equally accessible to everyone.
In Humanism: An Introduction, Jim Herrick writes:
The widest cause of secularization may be the steady change of thinking so that there is the expectation that reason and a consideration of cause and effect will help with explanations. Supernatural power began to be removed from explanations of the process of life or society in the seventeenth century, and although there may be a nod towards astrology or the crossed finger today, superstition is not seriously used in decision making. ...
Scientific thinking, which similarly developed in the seventeenth century, has been influential in bringing this change. We now see that tornadoes and earthquakes have rational explanations in terms of climatology and seismology rather than as divine punishments. Most people when deciding whether to take a new job, embark on a divorce, or simply plan a holiday will not seek divine guidance, but rather discuss with themselves or others the issues of cause and effect.
Herrick is addressing the process of secularization on a very personal level: the process by which individuals have gradually shed their reliance on religion for explanations, understanding, and structuring their lives. However much of a role that religion continues to play in people’s lives, it’s clear that it plays much less of a role than it used to. As Herrick notes, it’s uncommon today for people to consult religion for explanations of storms, to decide about a trip, and so forth.
Certainly this personal secularization played a role in the wider secularization of society. The more people are able to think, reason, and make decisions independently of religion, the more receptive — if not welcoming — they will be of secular institutions. Science has played an important role in this because it has so effectively demonstrated the power of secular processes. This has not, however, kept people from resisting secularization and seeking a return to a religious way of living.
At the same time, though, I wonder if perhaps Herrick is not overstating his case a bit. It may be true that things like astrology are not consulted like they once were, but they do remain popular. There are millions of people who continue to turn to psychics, astrologers, palm readers, and other “consultants of the supernatural/paranormal” when making a variety of decisions in their lives. Perhaps the numbers are lower in Britain, where Herrick lives, but they remain high in America.