1685-1753. Irish philosopher. The most brilliant theistic philosopher of his age, he was dean of Derry and later bishop of Cloyne. In an era when the sufficiency of reason, at the expense of revelation, was confidently asserted, he demonstrated that the church could outthink its critics. In his major work, Alciphron (1732), he showed that the problems of the Age of Reason could be solved only through a new understanding of the role of reason. He believed that ideas are the things which really exist. Material things exist only in so far as they are perceived. It is God who is responsible for the existence of ideas; they are not the products of our own minds. Berkeley was also a missionary enthusiast and unsuccessfully proposed a college in Bermuda.