Does Moll Flanders Know Whether Her Mother Is Cheerful?

The Gettier problem in Daniel Defoe’s novel

18th-century fleuron of The Fortunes and Misfortunes of Moll Flanders, Wikimedia Commons, public domain.

Moll Flanders is an early 18th-century novel written by Daniel Defoe. Moll is a fictional character whose famous conundrum is her discovery that her husband is her biological brother.

The “Gettier problem” is an epistemological question raised by Edmund Gettier in a 1963 paper, “Is Justified True Belief Knowledge?”, in which he questioned a traditional definition of knowledge — a justified true belief — as insufficient. Gettier died in 2021.

I described the philosophical problem in a separate article:

Toward a Better Epistemology: Why Do We Care About What We Know?

To present it generally: Gettier pointed out that, when we have reason to believe a certain proposition, we may formulate a vague statement about it, and the vague statement may turn out to be true, but for a different reason than we originally assumed.

For example, if I tell my roommate, “Don’t worry about the utility bill on the table; it’ll be affordable, and it isn’t due until the end of the month,” and I’m…