Prescriptivism is an approach to language centred on how it should be used. It contrasts with descriptivism, which is about describing how language is used. Prescriptivism has a bad reputation among linguists and the descriptively minded. I’m in the latter group, but I routinely apply prescriptive rules in my work as a copy-editor. It’s a more nuanced picture than is generally supposed.
I’m selective about the rules I enforce, dismissing the myths that bedevil English usage. I may apply a rule one day and not the next, adjusting to house style or other factors. I also edit texts to make them more inclusive – less ableist and more gender-neutral, for example. That too is prescriptivism, though it’s not usually categorized as such.
When people use language, they’re often influenced or guided by prescriptive advice, instruction, traditions, and norms. That influence, no matter how overt, conscious, or otherwise, must be part of how we describe language and its history. So in some ways descriptivism encompasses prescriptivism, or at least it should.
The complexity and apparent conflicts here derive in large part from the tendency to lump prescriptivism into a single category. I do this myself sometimes, for convenience. But by oversimplifying the nature and aims of prescriptivism, we invite confusion, category errors, and semantic muddles.
So how might we bring this fuzzy picture into better focus? One attractive option is proposed by linguist Anne Curzan in her book Fixing English: Prescriptivism and Language History (Cambridge University Press, 2014), which seeks to clarify the heterogeneous nature of prescriptivism and to give it its historical due:
Posted by Stan Carey 
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