Prescriptive grammar has spread linguistic insecurity like a plague among English speakers for centuries, numbs us to the aesthetic richness of non-standard speech, and distracts us from attending to genuine issues of linguistic style in writing.
Interpretation
Prescriptive grammar creates insecurity about language use, limiting appreciation of diverse speech styles.
John H. McWhorter argues that prescriptive grammar imposes rigid rules on language, fostering linguistic insecurity among speakers. This focus on correctness detracts from the beauty of non-standard speech forms and diverts attention from important considerations regarding writing style and effective communication.
In practice
In a speech about the evolution of language, you could use this quote to emphasize the need to embrace diverse forms of speech.
One summer morning at sunrise a long time ago I met a little girl with a book under her arm. I asked her why she was out so early and she answered that there were too many books and far too little time. And there she was absolutely right.
One principle problem of educating software engineers is that they will not use a new method until they believe it works and, more importantly, that they will not believe the method will work until they see it for themselves.
I did go through graduate school and I like to do research, to create something that has a certain objective solidity. The same thing influences my fiction to some degree, because, you know, my fiction is often based on history that I've read.
Everyone engaged in research must have had the experience of working with feverish and prolonged intensity to write a paper which no one else will read or to solve a problem which no one else thinks important and which will bring no conceivable reward - which may only confirm a general opinion that the researcher is wasting his time on irrelevancies.
Talent is a by-product of education; the quality of a country's human capital depends on it.
Do not believe what your teacher tells you merely out of respect for the teacher.
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