In the eighteenth and most of the nineteenth century, people in America known formally as philosophers were part of a wider dialogue that had three major components.
Most important were parish ministers, primarily in New England, who wrote on theology and participated in a conversation that embraced a religious élite in England and Scotland, and later in Germany. These clerics expounded varieties of Calvinist Protestantism. Jonathan Edwards was the most influential and talented member of this ministerial group, which later included Horace Bushnell and Ralph Waldo Emerson. But these two lived at a time when such thinkers were deserting their congregations and turning away from traditional Protestant doctrine. Because these sages were unconnected to institutions of higher education, I have sometimes called them amateurs, although this term embraces a wider collection of individuals, some of whom were less religious, or were on the fringes of the emerging system of advanced academic training in the late eighteenth and early nineteenth centuries.
The second major component of American speculative thought was located in one part of this system, the seminaries that grew up in the Northeast, the old Midwest, and the South throughout the nineteenth century. Often independent entities unconnected to American colleges, these institutions were, aside from law and medical schools, the only places where an aspiring young man could receive instruction beyond what an undergraduate received; they arose to train a professional ministry. The specialists in theology at these centers gradually took over the role that the more erudite ministry had played. Leonard Woods of Andover Theological Seminary; Henry Ware of the Harvard Divinity School; Nathaniel William Taylor of the Yale Divinity School; Charles Hodge of the Princeton Theological Seminary; and Edwards Amasa Park of Andover belong to this cadre.