Christadelphianism traces its origins to John Thomas (1805–1871), who emigrated to North America from England in 1832. Following a near shipwreck he vowed to find out the truth about life and God through personal Biblical study. Initially he sought to avoid the kind of sectarianism he had seen in England. In this he found sympathy with the rapidly emerging Restoration Movement in the United States at the time. This movement sought a reform based upon the Bible alone as a sufficient guide and rejected all creeds. However, this liberality eventually led to dissent as John Thomas developed his personal beliefs and began to question mainstream orthodox Christian beliefs. While the Restoration Movement accepted Thomas's right to have his own beliefs, when he started preaching that they were essential to salvation, it led to a fierce series of debates with a notable leader of the movement, Alexander Campbell. John Thomas believed that scripture, as God's word, did not support a multiplicity of differing beliefs, and challenged the leaders to continue with the process of restoring 1st-century Christian beliefs and correct interpretation through a process of debate. The history of this process appears in the book "Dr. Thomas, His Life and Work" (1873) by a Christadelphian, Robert Roberts.