Logical Reasoning

PT118 · S1 · Q8 Trust, which cannot be sustained

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Trust, which cannot be sustained in the absence of mutual respect, is essential to any long-lasting relationship, personal or professional.

Statements

Long-lasting → trust → mutual relationship respect (personal or professional)

Long-lasting → natural affinity relationship (personal)

The last sentence is just a restatement of what we already have here (long-lasting personal relationship requires trust, mutual respect, and affinity), so we don't need to notate it separately.

Evaluate

Since this is Must Be True, we're primarily reading for Conditional or Quantitative ideas (keeping an eye out for Causality, otherwise).

We see conditional words galore: "can't be sustained in the absence of" (introduces right side) "essential" (the essential thing goes on right side) "require" (introduces right side) "if" (introduces left side) "must" (introduces right side)

Are there repeated ideas? If so, it's probably worth diagramming, to see if stuff chains together. If not, it's probably worth just re-reading the paragraph and then looking back at the paragraph as needed as we survey answer choices.

Yes, there are repeated ideas: mutual respect, affinity, personal relationship. So let's get diagramming.

All of these expressions ... X can't be sustained in the absence of Y Y is essential to X X's additionally require Y X must be supported by Y ... mean the same thing: "X requires Y"

if you don't have Y, can't have X ~Y → ~X X requires Y X → Y

Goal

Look for something derivable from these conditionals. Beware illegal reversals or negations, and get rid of out of scope ideas.

If the statements above are true, then which one of the following must also be true?

Correct
A friendship supported solely by
Why this is right
If something is supported solely by mutual respect and and trust, then it isn't supported by everything else in the world (including affinity). Thus, according to the last sentence, this friendship (a personal relationship) cannot endure (will not be long-lasting).
Skill tested: Must be True · how this choice captures the argument's function is the move to repeat next time.
65% picked this
In the context of any
Reversed Logic
We were told that trust ? mutual respect (trust requires / presupposes mutual respect) This answer is selling us on the reversal, mutual respect ? trust
16% picked this
If a personal relationship is
Reversal
This is reversed logic on the final sentence. We know that long term relationships require mutual respect and affinity, personal mutual respect relationship ? and endures affinity And this answer choice is giving us that conditional in illegal backwards form.
17% picked this
Personal relationships, such as marriage
Unknown Comparison: longer-lasting
"long-lasting" was used only in an absolute, yes/no sense. We can't switch into talking about it in a Relative sense, and we have no way of comparing the longevity of personal vs. professional relationships.
1% picked this
Basing a marriage on a
Reversal
This is again reversing something we're told in the last sentence. An enduring marriage would require affinity (and mutual respect). But this answer is acting like affinity by itself guarantees an enduring marriage.
1% picked this

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