Our study explored 250 international teachers' definitions of the English-language literary canon. Questionnaire respondents defined the literary canon, rated the aesthetic value of 22 prose texts, and gave the 22 texts a "canon rating" to indicate the extent to which they thought the text was canonical. We found that teachers find some value in the literary canon, as defined by them, whereas others called for the canon to be expanded or disbanded. We report that perceived aesthetic quality appears to be a dimension of canon, and that authors seem to be admitted to the canon posthumously. The work provides a rare insight into teachers' definitions of canon -- information that helps those who set curricula, and those in the wider education ecosystem, to understand the complex meanings underpinning requests for students to study more or fewer canonical texts.