Paraphrase Macbeth Quotes & Sayings

I once mentioned in a school report, how a young man in one of our English training colleges having to paraphrase the passage in Macbeth beginning,

Can'st thou not minister to a mind diseased?

turned this line into, "Can you not wait upon the lunatic?" And I remarked what a curious state of things it would be, if every pupil of our national schools knew, let us say, that the moon is two thousand one hundred and sixty miles in diameter, and thought at the same time that a good paraphrase for

Can'st thou not minister to a mind diseased?

was, "Can you not wait upon the lunatic?" If one is driven to choose, I think I would rather have a young person ignorant about the moon's diameter, but aware that "Can you not wait upon the lunatic?" is bad, than a young person whose education had been such as to manage things the other way — Matthew Arnold