This "miracle birth" has traditionally been seen as a result of Birmingham's status as a stronghold of religious Nonconformism, creating a free-thinking culture unconstrained by the established Church of England. This accords with wider historical theories such as the Merton thesis and the Weber thesis, that see Protestant culture as a major factor in the rise of experimental science and industrial capitalism within Europe. Birmingham had a vigorous and confident Nonconformist community by the 1680s, at a time when freedom of worship for Nonconformists nationally had yet to be granted; and by the 1740s this had developed into an influential group of Rational Dissenters. Around 15% of households in Birmingham were members of Nonconformist congregations in the mid-18th century, compared to a national average of 4–5%. Presbyterians and Quakers in particular also had a level of influence within the town that was disproportionate to their numbers, customarily holding the position of Low Bailiff – the most powerful position in the town's local government – from 1733, and making up over a quarter of the Street Commissioners appointed in 1769, despite being legally barred from holding office until 1828. Despite this, Birmingham's Enlightenment was by no means a purely Nonconformist phenomenon: the members of the Lunar Society had a wide range of religious backgrounds, and Anglicans formed a majority of all sections of Birmingham society throughout the period.