What is the difference between a philosophical novel and a novel of ideas?

Question

Wikipedia calls the novel of ideas a subgenre of philosophical fiction, without defining the first term. The Routledge Encyclopedia of Narrative Theory (2010) uses the terms "novel of ideas" and "philosophical novel" interchangeably. In articles published together in the New York Times in 2016 under the headline "Whatever Happened to the Novel of Ideas?", Benjamin Moser also uses the terms to mean the same thing, and Pankaj Mishra, while eschewing the word "philosophy", draws no distinction between them. Writing in the Financial Times in 2012, Jenny Erdal describes the two forms as "close cousin(s)", but she does not explain the difference.

There does, however, seem to be general agreement that the novel of ideas is quite rare nowadays.

Since not all ideas are philosophical, I do not favour a definition of the novel of ideas as a type of philosophical novel, it seeming that if one is a subtype of the other then the relationship should be the converse. But in that case, what definitions might we use? And if neither wholly includes the other, and therefore each has instances that are not instances of the other, how might we define the two genres as "close cousins"?

Google's Ngram viewer returns the following for the use of the two terms over time:

I have looked briefly at a number of other sources, including encyclopedias. While several define the two terms as equivalent, several others do not. But I have so far found only one source that offers clearly contrasting definitions, namely Leszek Kolek's 1975 PhD thesis. The author defines one of his aims as being to provide "a definition and description of the genre called 'novel of ideas' on the basis of (Aldous) Huxley’s fiction". Achieving his aim, he describes its distinctive features as being found in

• its “material”: that is, explicit ideas appearing in the fictional reality;
• a reduced semantic significance of character and plot;
• a semantic and structural balance between explicit and implicit modes of presentation,

where an explicit idea is "an abstract, syncretic and explicit statement analysed in essayistic utterances of the characters, the narrator’s comments, and in various forms of quotations" (p.106).

He goes on to say that the novel of ideas differs from the philosophical novel "owing to the syncretic character of explicit ideas" and its "lack of a 'thesis'", the implication being that a philosophical novel shares the above three features except that its explicit ideas are non-syncretic and it contains a thesis. (It could also be that he means to suggest that the expression of ideas in a philosophical novel is achieved using means that have a greater proportion of the implicit rather than the explicit, but he does not say so explicitly.) Kolek qualifies the distinction, however, by acknowledging that "we" lack a precise definition of the philosophical novel (p.107).

How far this gets us, I am not sure.

Answer 1

My go-to source for authority on a matter like this is J.A. Cuddon's A Dictionary of Literary Terms and Literary Theory. Here is the definition there for "novel of ideas":

A vague category of fiction in which conversation, intellectual discussion and debate predominate, and in which plot, narrative, emotional conflict and psychological depth in characterization are deliberately limited. Such a form of novel is perhaps best exemplified by Aldous Huxley's Crome Yellow (1921), Point Counter Point (1928) and After Many a Summer (1939).

I find it amusing that it is immediately described as a "vague category," hence the need for this question. In my brief research I kept coming back to Huxley, which might also explain the n-gram results and which supports some of what you found in your research. I can't think of much else that fits this definition. I once checked out (but never actually read) a book by Owen Barfield, a lesser-known Inkling, called Worlds Apart that probably is also a novel of ideas. Nothing else comes to mind.

The problem with these terms arises when "novel with ideas" comes to mean "novel of ideas" and thus anything philosophical in literature, which includes a lot of famous literature, comes to mean the latter. Case in point, this list on Good Reads of novels of ideas starts with 1984, a novel that does anything but fit Cuddon's definition. This maybe hits at the crux of the problem: the textbook definition does not align with the popular usage of the term.

In sum, the pedantic literary critic (which I have no shame in admitting to being) sees "novel of ideas" as a classification with limited scope and few examples. The general public, it would seem, conflates "philosophical novel," an incredibly broad category, with "novel of ideas."

Answer 2

As well as Leszek Kolek's 1975 work, I have now found a second text that offers contrasting definitions of the two terms: Timothy Bewes's "What is 'Philosophical Honesty' in Postmodern Literature?" (New Literary History, vol.31, no.3, 2000, pp. 421-434). Bewes's article is referred to in David Cunningham's entry on "Philosophical Novel" in the Encyclopedia of the Novel (2011), published by Wiley Blackwell. Unlike every other author I have consulted, Bewes states that the novel of ideas is "one of the most prevalent of contemporary literary forms".

Bewes defines the philosophical novel (PN), in contradistinction to the novel of ideas (NOI), as having no authorial predetermination, instead comprising a meditation. The author of a PN, he says, seeks to meet the reader halfway, refusing to play to the gallery and appeal to the market.

Seemingly ignoring the fact that the term NOI was used a long time before the coinage of "postmodern", he then says that the NOI is "a characteristic of postmodernity": whereas the PN is "modern", the NOI is "postmodern". In his view, the NOI manifests on a wide scale as the only form in which "philosophical honesty" can appear in "postmodern literature" when "'market-led' dishonesty" has become a "structural feature of the cultural and philosophical landscape". In short, he views the NOI as a vehicle for telling the reader the ideas that he wants to hear.

I'm not at all in tune with Bewes's viewpoint, but I thought it was worth referring to here because he is one of very few authors to offer contrasting definitions of the PN and NOI.