PrepTest 121

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
(1) Language → Verbal signs for objects AND Verbal signs for feelings
(2) Animals-some-Verbal sign for feelings
(3) Ask for apple or egg by name → Human
(4) Verbal signs for objects → Ability to distinguish between different objects → Conceptual thought

Answer Anticipation:
This stimulus is a mess, but it's a conditional mess, so we can work with the statements!

The argument opens with a conditional ("requires") that establishes two necessary conditions for language. Since they're connected with AND, they're both present when language is present, so we can split these up—and since one of the two shows up as the sufficient condition in conditional #4, we should do that:
(1a) Language → Verbal signs for objects
(1b) Language → Verbal signs for feelings

From there, we get a some statement ("many") which doesn't overlap with our conditionals, so we can likely disregard it.

We then get another conditional about humans. The two examples provided are examples of using verbal signs for objects, but it's unclear if the argument is treating this as establishing that only humans can use verbal signs for objects, and thus only humans can use language. Let's put a pin in that and come back to it if needed.

Instead, let's focus on that last statement, which provides a conditional chain. Verbal signs for objects require an ability to distinguish objects ("requires" introducing a necessary condition), "which in turn requires" (adding a necessary condition to the conditional chain) conceptual thought. Adding statement 1a to the beginning of this chain, we get:
Language → Verbal signs for objects → Distinguish objects → Conceptual thought

So Language → Conceptual thought (or not Conceptual thought → not Language) is likely our correct answer.

Answer Explanation:
This answer matches our anticipation perfectly. Splitting the first conditional and adding it to the conditional chain in the last sentence yields this inference, so it's correct.

Key Takeaway:
Conditional logic will save your life. Not really. Well, almost certainly not. But it will get you points on the LSAT, so learn it and apply it when appropriate!

Incorrect. Conceptual thought is given as only a necessary condition, so this answer is wrong in establishing it as a sufficient condition.

Incorrect. The argument never connects conceptual thought and feeling, so this answer is incorrect.

Incorrect. Humans are only a necessary condition in this argument, so this answer treating them as a sufficient condition ("All humans") is incorrect. Some humans are capable of conceptual thought (those who can ask for an egg/apply by name), but there's no statement strong enough to support that this is true of all of them.

Incorrect. We don't know enough about the vocal expressions of animals to draw this conclusion. Additionally, "Conceptual thought" is a necessary condition in the stimulus, so we can't infer anything about "not Conceptual thought" as a necessary condition—that's an illegal negation.