Invention: Canons of Rhetoric


Invention concerns finding something to say (its name derives from the Latin invenire, “to find”). Certain common categories of thought became conventional to use in order to brainstorm for material. These common places (places = topoi in Greek) are called the “topics of invention.” They include, for example, cause and effect, comparison, and various relationships.

Invention is tied to the rhetorical appeal of logos, being oriented to what an author would say rather than how this might be said. Invention describes the argumentative, persuasive core of rhetoric. Aristotle, in fact, defines rhetoric primarily as invention, “discovering the best available means of persuasion.” An important procedure that formed part of this finding process was stasis.

Sample Rhetorical Analysis: INVENTION

In describing the state of humanity, Blaise Pascal aphoristically states

We desire truth, and find within ourselves only uncertainty. We seek happiness, and find only misery and death. We cannot but desire truth and happiness, and are incapable of certainty or happiness.

In these nicely parallel claims, Pascal follows a similar pattern of development based on the identification of an antecedent and its inevitable consequence. [antecedent/consequence is a common topic of invention]. We must ask ourselves, Are these the necessary antecdents to the stated consequences? Does his concision betray a larger complexity? Aren’t these consequences the causes themselves for pursuing what he refers to as antecedents?

Related Figures

See Also

Sources: Cic. De Inv. passim

The Five Canons of Rhetoric:
invention  | arrangement  | style  | memory  | delivery

The information on this page comes from: Gideon O. Burton, Brigham Young University. EIL is grateful for his excellent “Silva Rhetoricae” (, which is licensed under a Creative Commons Attribution 3.0 License. Image added by EIL staff.


How do you spark new ideas? Do you make mind maps or outlines as you brainstorm?