Logical Reasoning

PT112 · S3 · Q12 Vague laws set vague limits

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Vague laws set vague limits on people’s freedom, which makes it impossible for them to know for certain whether their actions are legal.

Conclusion (thus)

Under vague laws people cannot feel secure.

Evidence

Vague laws set vague limits on people's freedom. This makes it impossible for them to know whether their actions are legal.

Evaluate

We're trying to prove that if you live under vague laws, you cannot feel secure. Did the evidence provide a proving mechanism for that language? In other words, do we have a rule that looks like,

If xyz, then cannot feel secure?

No, not yet. So the correct answer 100% must provide us with such a rule.

What do we know about vague laws? Two things. - set vague limits on personal freedom - impossible to know for certain whether your actions are legal

Goal

Since the correct answer is supposed to combine with our premises and allow us to derive the idea that "under vague laws, cannot feel secure", there are two possible correct answers:

if something sets vague → cannot limits on personal freedom feel secure

if imposs to know for sure → cannot whether actions are legal feel secure

12.

The conclusion follows logically if which one of the following is assumed?

  1. Correct

    People can feel secure only

    Why this is right

    The word "only if" always indicates the necessary idea that goes on the right of the arrow, so this answer looks like this: can feel secure → know for sure whether actions are legal We're trying to prove "cannot feel secure", so this rule looks useful! If we contrapose (as we usually do for our correct answer), we'll have that on the right side of the arrow, where the Conclusion language belongs. don't know for sure → cannot feel whether actions are legal secure We know that under vague laws, it's impossible to know for certain whether one's actions are legal. According to this rule, then, under vague laws one cannot feel secure. We've proven the conclusion!

    Skill tested: Sufficient Assumption · how this choice captures the argument's function is the move to repeat next time.

    66% picked this

  2. If people do not know

    Too Weak

    We need an answer that provides a rule that can prove "cannot feel secure", so it should have that language on the right of the arrow. This answer is putting "might not feel secure" on the right of the arrow, which isn't strong enough to logically guarantee "cannot feel secure". Weak language like "some / might / can / not all" is almost always wrong on Sufficient Assumption, Strengthen, Weaken, and Paradox.

    11% picked this

  3. If people know for certain

    Illegal Negation

    We need an answer that provides a rule that can prove "cannot feel secure", so it should have that language on the right of the arrow. This answer is putting "can feel secure" on the right of the arrow, so it will be worthless to us. This answer is the typical illegal Reversal / Negation trap answer we always see on Sufficient Assumption. We'd love to have a rule that says, "If people don't know whether their actions are legal, then they can't feel secure". This answer is an illegal negation of that.

    12% picked this

  4. People can feel secure if

    Illegal Negation

    We need an answer that provides a rule that can prove "cannot feel secure", so it should have that language on the right of the arrow. This answer is putting "can feel secure" on the right of the arrow, so it will be worthless to us. The word "if" always indicates the sufficient condition that goes on the left of the arrow, so this looks like this: Governed by laws → Can feel secure that are not vague This answer is just an Illegal Negation of the conclusion, which says this: Governed by laws → Cannot feel secure that are vague

    8% picked this

  5. Only people who feel secure

    Illegal Negation

    We need an answer that provides a rule that can prove "cannot feel secure", so it should have that language on the right of the arrow. This answer is putting "can feel secure" on the right of the arrow, so it will be worthless to us. The word "only / only if" always indicates the necessary condition that goes on the right of the arrow ("the only" indicates a sufficient condition that goes on the left). So this answer looks exactly like (C): Know whether → Can feel secure actions are legal This answer is an Illegal Negation of what our correct answer looks like: don't know whether → Cannot feel actions are legal secure

    2% picked this

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