Why does the poet say that the schoolmaster in "The Deserted Village" was both kind and severe?
The speaker is attempting to give us a rounded portrait of the eponymous village's schoolmaster. Though much of the poem's style is gently mocking, there's no doubt that the speaker generally admires the schoolmaster—this man who brought some much-needed learning and erudition into this remote rural backwater.
That being the case, the speaker refers to the schoolmaster's kindness, which is mentioned just after we've been told about how severe and stern he was towards his pupils. There's clearly something remarkable about this man who dominated village life for so many years. A big fish in a little pond, he greatly impressed the unlettered villagers with his grasp of Latin and his capacity for reasoned argument.
The schoolmaster was clearly at the center of community life. And by portraying him in a generally rounded, sympathetic way, the speaker wants us to feel that something has been lost by his passing. To a considerable extent, the schoolmaster was the village—the village's very heart and soul. And now that he is gone, so too is the village and all the pupils he taught over the years.
Stern and strict though he may have been, the schoolmaster left big tracks behind: not just due to his knowledge, or his gifts as a teacher, but because of his kindness. Had he not displayed such kindness, it is unlikely that he would've been remembered with anything like the same degree of affection. And if there's one thing that this poem is concerned with, it's the importance of remembering the past.
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