A colonnaded circular monument to the right was raised in the memory of Dugald Stewart, professor of moral philosophy at the University of Edinburgh in the 1780s.
There were no monuments erected in honor of Dugald Stewart.  
mnli hypothesis: There were no monuments erected in honor of Dugald Stewart.   premise: A colonnaded circular monument to the right was raised in the memory of Dugald Stewart, professor of moral philosophy at the University of Edinburgh in the 1780s.