The doctrine that certain concepts are simply convenient fictions(noun)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "fictionalism" in a sentence
"Let us call the fictionalism according to which there is a literal use of the sentences in question with which the ordinary use contrasts use fictionalism; call the other meaning fictionalism."
"Let's move on now to a discussion of fictionalism, which is the last option for nominalists."
"Craig then goes on to discuss an a posteriori establishment of Premise #1, but Craig treads carefully here: "I remain uncertain of this argument ... which would require us to reject various nominalistic alternatives to conceptualism such as fictionalism, constructabilism, figuralism, and so forth."