Abstract
In chapter one of the twelfth book of his Institutio oratoria, Quintilian goes out of his way to defend his meta-rhetorical thesis that only a morally good man can be called an orator. This article argues that, from a logical point of view, his reasoning has many leaks and is ultimately not convincing. What is more, Quintilian seems to have been conscious about the fallaciousness of his own argument. So this article goes on to search for an explanation of his resolution to take upon himself the herculean task to establish the validity of his paradoxical thesis.