Inventio is the system or method used for the discovery of arguments in Western rhetoric and comes from the Latin, meaning "invention" or "discovery".

It is the first of five canons of classical rhetoric (the others being dispositio, elocutio, memoria, and pronuntiatio) that concern the crafting and delivery of speeches and writing.

One of the oldest criticisms of rhetoric is that as an art it has no proper subject matter. In other words, an orator might speak on any topic, with his success being measured purely on the brilliance of his rhetorical skills. This aspect of rhetoric is one reason why Plato attacked what he saw as empty rhetoric on the part of sophist philosophers, such as Gorgias.

Aristotle, in his works on rhetoric, answered Plato's charges by arguing that reason and rhetoric are intertwined ("Rhetoric is the counterpart of Dialectic" is the first sentence of his Rhetoric). In Aristotle's view, dialectic reasoning is the mechanism for discovering universal truths; rhetoric is the method for clarifying and communicating these principles to others. And in order to communicate effectively, an orator must be able to assemble proper arguments that support his thesis.

Inventio, therefore, is the systematic discovery of arguments. Aristotle, as well as later writers on rhetoric, such as Cicero and Quintilian, devoted considerable attention to developing and formalizing the discipline of rhetorical invention. Two important concepts within invention were topoi and stasis.

Topoi

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In classical rhetoric, arguments are obtained from various sources of information, or topoi (from the Greek for "places"; i.e. "places to find something"). Topoi are a set of categories that help delineate the relationships among ideas; Aristotle divided these into "common" and "special" groups.

In the common group could be found such categories as laws, witnesses, contracts, oaths, comparisons of similarity, difference, or degree, definitions of things, division of things (whole/parts, for instance), cause and effect, and other items that could be analyzed, researched or documented.

Modern writers and students use these topics, as well, when discovering arguments, although today more emphasis is placed on such things as scientific facts, statistics, and other "hard" evidence. Classical rhetoricians saw many areas of inquiry that today's writer might view as being purely in the province of "logic" — developing syllogisms, finding contradictions, and so on — as being of equal or greater importance.

Special topoi included such concepts as justice or injustice, virtue, good, and worthiness. Again, these are areas of inquiry seen by many today as belonging to other arts, but from Greek times through the Renaissance, these were considered integral to the study and practice of rhetoric.

Stasis

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The procedure known as stasis was another important part of the invention process. This involved the practice of posing and exploring questions relevant to clarifying the main issues in the debate. There were four types of stasis: definitional, conjectural, translative, and qualitative. For instance, a lawyer defending someone accused of damaging property might pose the following questions:

• Question of fact: did the person damage the item? (conjectural)
• Question of definition: was this the damage minor or major? (definitional)
• Question of quality: was he justified in damaging the item? (qualitative)
• Question of jurisdiction: should this be a civil or criminal trial? (translative)

Through the application of this process, as well as using the relevant topoi, the orator would be able to construct not just elegant arguments, but ones that were well-reasoned and well-researched. For example, to answer the second question, the attorney would need to ascertain additional things: how should the degree of damage be measured? does the law specify distinctions between degrees of damage? was there some remedy to the damage that could easily set things right? and so on.

See also

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• Rhetoric

External links

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• PDF edition of Janice Lauer's Invention in Rhetoric and Composition

Rhetoric

Inventio | Inventio