Institutio Oratoria

The most effective kind of enthymeme seems however to be that in which a reason is subjoined to a dissimilar or contrary proposition as in the following passage from Demosthenes [*](in Androt. § 7; in Aristocr. § 99. ) :

For if at any time an act has been committed contrary to law and you have imitated it, it does not therefore follow that you should go scot free; on the contrary it is an additional reason why you should be condemned. For if any of those who transgressed the law had been condemned, you would not have proposed this, and further, if you are condemned, no one else will propose anything of the kind.