Of, pertaining to, or supporting fictionalism(adjective)
One who subscribes to fictionalism, the belief that certain concepts are simply convenient logical fictions(noun)
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Use "fictionalist" in a sentence
"A certain kind of fictionalist might claim that the real meaning of “Stealing is wrong” should be rendered in the cohortative mood (which in English is not grammatically distinguished from imperative): “Let's pretend that stealing is wrong.”"
"In believing that possible worlds do not exist, Armstrong is a kind of fictionalist about possible worlds, and so he calls himself (1989,"
"With all the commotion concerning Palin's alleged revisionist approach to Paul Revere, what has gone completely unnoticed is that her comment on Revere had more to say with Palin's admiration for the late Argentine fictionalist, Jorge Luis Borges, than anything else."