Trust, which cannot be sustained in the absence of mutual respect, is essential to any long-lasting relationship, personal or professional. However, personal relationships, such as marriage or friendship, additionally require natural affinity. If a personal relationship is to endure, it must be supported by the twin pillars of mutual respect and affinity.
If the statements above are true, then which one of the following must also be true?
(A) A friendship supported solely by trust and mutual respect will not be long-lasting.
(B) In the context of any professional relationship, mutual respect presupposes trust.
(C) If a personal relationship is supported by mutual respect and affinity, it will last a long time.
(D) Personal relationships, such as marriage or friendship, are longer-lasting than professional relationships.
(E) Basing a marriage on a natural affinity will ensure that it will endure.
Source: LSAT
As you read a stimulus, listen for the language of necessity: “essential to”; “require”; “must be”; “cannot be sustained in the absence of.”
All four of the above phrases appear here, and make it clear that the author is interested in detailing necessary characteristics of certain human relationships. Trust requires mutual respect, and all enduring relationships require trust. One particular type—the truly personal—also requires affinity. So the enduring personal relationship requires both respect (necessary for trust and endurance) and affinity (necessary for any personal bond). It’s all pretty tidy and should make sense. Let’s look for the one choice that must be true.
(A) We need look no further. Friendship is specifically named as one type of relationship that requires more than trust and respect: it requires affinity, and in affinity’s absence it will not endure. (A) directly follows from the stimulus.
(B) distorts the ideas. A professional relationship needs trust, which in turn needs mutual respect. But that’s a far cry from saying that the latter presupposes the former.
(C) The classic confusion of necessity and sufficiency. Contrary to (C), respect and affinity are necessary for a long-lasting personal relationship but may not be sufficient for it; other factors may be needed as well.
(D) is a classic example of what we’ve called “irrelevant or unwarranted comparison.” Nowhere is a longevity comparison made between the two types of relationships.
(E) is both incomplete (a marriage requires more than just affinity) and presumptuous (even with a combination of affinity and respect, an enduring marriage is by no means certain).