Bonner adds (p. 3):

     It is in the Rhetorica  of Cicero, the Institutio Oratoria  of 
     Quintilian, and the later Greek and Roman rhetoricians, 
     that specific examples of subjects of theses  are found. 
     They represent the major problems of the world and its 
     meaning, of human life and conduct, which the Greeks 
     debated through the ages, from the cities of Asia Minor 
     to the groves of the Academy, from the Garden and the 
     Porch to the villas of Italy and the colonnades of Rome.

     The reason for bringing up the character of scholastic 
form is that from the twelfth to the sixteenth centuries this 
kind of highly oral activity broke away from the grammatica  
that formed the base of monastic and later humanist 
procedures. For grammatica  is concerned very much with