This accomplished man condescended to think of a young girl, and take the pains to talk to her, not with absurd compliment, but with an appeal to her understanding, and sometimes with instructive correction.
For he had been as instructive as Milton’s "affable archangel;" and with something of the archangelic manner he told her how he had undertaken to show (what indeed had been attempted before, but not with that thoroughness, justice of comparison, and effectiveness of arrangement at which Mr. Casaubon aimed) that all the mythical systems or erratic mythical fragments in the world were corruptions of a tradition originally revealed.
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And very instructive.
Rick Yancey -- The 5th Wave
"Let’s table that thought for a second, because that’s instructive, the fact that you were aware of the groups, but didn’t seek them out.