Illegal Negation v. Reversal

[SamT18]

Because the contrapositive of an illegal/mistaken negation is an illegal/mistaken reversal (and vice versa), is there ever a possibility on a match the flaw question type where the flaw is, for example, an illegal negation and the correct answer choice is disguised as an illegal reversal? Or, do the testmakers recognize these flaws as two, distinct errors that do not overlap?

Thanks!

[ohthatpatrick]

There's almost no chance ever that two answers would split hairs between those two sides of the same coin.

The only time it's ever happened was once or twice on a Match the Flaw question.

Here's a post in which I refer to it happening on another question (but the actual question here might also be an example):
https://www.manhattanprep.com/lsat/foru ... t8171.html

And here's the question I think I was referring to:
https://www.manhattanprep.com/lsat/foru ... t7639.html


As you'll see if you read those posts, even though the illegal negation / reversal are technically the same, since the question stem for Match Flaw can be worded "which of these most effectively demonstrates / replicates the flawed reasoning", the more exact match can still be thought of as superior.

[DavidP514]

Are all mistaken reversals mistakes a necessary for sufficient and are all mistaken negations mistakes a sufficient for necessary?

Many forums state that a mistaken reversal is when you mistake a necessary condition for a sufficient condition and that te mistaken negation is the opposite.

Is this always the case?

Mike Kim gives an example that seems to contradict this rule: "If you finish college, you are certain to be financially successfully. Therefore, if you want to be be financially successful, you must finish college" In his book. he states that this is Mistakes a sufficient for a necessary"

He gives other examples such as " Coffee helps one stay awake. Therefore, if one wants to stay awake one needs to drink coffee" or "Every student in Mrs. W class went to the museum. Since Sean went to the museum, he must be in Mrs. Wilber' Class"

These all seem to contradict the idea that mistaken reversal are all mistakes a sufficient for necessary