Question

たこ

ポレポレの例題26番についてです
なぜif not〜の節はofまでなんですか？参考書の説明やYouTubeで調べましたがよく分かりませんでした
positiveで切っても良くないですか？

例題26
There is general apathy to if not positive distrust of
FAU
science itself as a search for truth; for, to the ordinary
010
American, science is identified with mechanical inventions.
Ask an American to name the greatest scientist of this
country and he will very likely reply, "Edison." As a
nation, we respect only the practical application of science
and have regard for the efforts of inventors and promoters
rather than those of the scientific discoverers.
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