E.D. Hirsch, Jr.:

I am sure that the power of vested interests is vastly exaggerated compared with the gradual encroachment of ideas…. Soon or late, it is ideas, not vested interests, which are dangerous for good or evil.
—J. M. Keynes
The General Theory of Employment,
Interest, and Money
Consider the following sentence, which is one that most literate Americans can understand, but most literate British people cannot, even when they have a wide vocabulary and know the conventions of the standard language:
Jones sacrificed and knocked in a run.
Typically, a literate British person would know all the words in the sentence yet wouldn’t comprehend it. (In fairness, most Americans would be equally baffled by a sentence about the sport of cricket.)