Reductio ad absurdum is a kind of argument with which one argues for one’s own position by revealing the absurdity of an opponent’s position–one tries to reduce the opponent’s position to absurdity. For more information on reductio ad absurdum, click here.
William Blake makes excellent use of this argumentative structure in at least two pieces of writing:
In the first half (section a) of this early prose work, Blake employs a reductio ad absurdum strategy to show the kinds of absurdities which result from the belief that all of a person’s mental life is the product of sensory experience (a view Blake did NOT hold). In the second half of this work (section b), Blake makes his positive case: because our imaginations are filled with dreams and ambitions which seem more than just copies of what we perceive, we all must have some other infinite, creative potential in us.
In this poem–a kind of productio ad absurdum–Blake reveals the kind of troubles that can result from repressed anger.
“The Chaff,” by W. S. Merwin (in The Carrier of Ladders, collected in The Second Four Books, p. 219).