Among these were to be found the most sordid opportunism and the most heroic self-effacement, the crassest supernaturalism and - the loftiest conceptions of practical morality.
We feel its presence in his earliest notable work, The Rationale of Religious Enquiry, 1836; and may there see the rigour with which it applied audacious logic to narrow premisses, the tenacity with which it clung to a limited literal supernaturalism which it had no philosophy to justify, and so could not believe without historical and verbal authority.
Teller's writings present rationalism in its course of development from biblical supernaturalism to the borders of deistical naturalism.
Seeking to establish for himself a middle position between rationalism and supernaturalism, he declared for a "rational supernaturalism," and contended that there must be a gradual development of Christian doctrine corresponding to the advance of knowledge and science.
Indeed in 1864 he was recognized as leader of the radicals after his reply to Dr Hedge's address to the graduating students of the Divinity School on Anti-Supernaturalism in the Pulpit.
Meanwhile he did much editing and compiling, and produced, among other works in prose, The Stranger in Lowell (1845), Supernaturalism in New England (1847), Leaves from Margaret Smith's Journal (1849), a pleasing treatment in old-style English of an early Colonial theme.
In 1886 some of its professors published Progressive Orthodoxy, a book which made a great stir by its liberal tone, its opposition to supernaturalism and its evident trend toward the methods of German "higher criticism."
On the other hand, not merely agnostics like Leslie Stephen but Christian theologians of the Left like Ernst Troeltsch regard it as the time when supernaturalism began decisively to go to pieces, and the " modern " spirit to assert its authority even over religion.
Another American influence, potent in reducing the rigid though limited supernaturalism of Belsham and his successors, was that of Theodore Parker (1810-1860).
The aim of the work was to reform Protestant theology by means of the fundamental ideas of the Reden, to put an end to the unreason and superficiality of both supernaturalism and rationalism, and to deliver religion and theology from a relation of dependence on perpetually changing systems of philosophy.