Pinning down precisely what classical anarchism means is a tricky task. Richard Day associates classical anarchism with writers often regarded as canonical: Godwin, Proudhon and Bakunin as well as Kropotkin. To take another example, Paul McLaughlin argues that William Godwin, Pierre-Joseph Proudhon and Max Stirner were its key intellectual influences. Benjamin Tucker and Leo Tolstoy are sometimes described as classical anarchists but tend to have bit parts in the anarchist canon. On the other hand, Emma Goldman, whose exclusion from the canon is notorious, tends to be grouped with Gustav Landauer and sometimes Stirner, as pre-post-anarchists. Day, unusually, defends Kropotkin as the first post-anarchist to emerge from the canon. Inclusion in the canon does not lead to the automatic conferral of classical status. Similarly, it is possible to be put in the box marked classical without having a clearly canonical standing.

That Kropotkin is a canonical thinker is uncontentious. He was identified in Eltzbacher's study and, some fifty years later, in George Woodcock's Anarchism, a book that has played a key role in the canon's construction. Although Eltzbacher believed that it was only possible to gain an intimate knowledge of anarchism by the investigation of ‘less notable’ teachings as well as by the ‘most prominent’, Kropotkin emerged as one of seven sages of anarchism and a key referent for the construction of anarchist ideology. A recent poll confirmed his top ranking in the anarchist canon. Significantly, when compared to the other sages, he often appears as the least anarchic. In Woodcock's words, Kropotkin gave ‘the doctrine a concreteness and a relevance to everyday existence that it rarely shows in the writings of Godwin, Proudhon, or Bakunin’.

Kropotkin's identification as a classical thinker undoubtedly owes something to his inclusion in the canon but the classification also touches on understandings of anarchist traditions and the history of the anarchist movement that are not always explicit. As well as referring to a theoretical canon, classical anarchism sometimes also refers to a unifying idea, variously described as a theory of ‘structural renewal’, ‘the dream of society without the state’ and scepticism towards authority.