Logical Reasoning

PT153 · S2 · Q13 The use of ordinary dictionaries

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The use of ordinary dictionaries in interpreting the law is justified in the same way that chemists use the periodic table.

Conclusion (justified = opinion)

Using ordinary dictionaries to interpret the law is justified, just like a chemist using the periodic table.

Evidence

The periodic table is a convenient source of agreed-upon background info that a chemist can use on the problem on which she's working.

Similarly, an ordinary dictionary can be used by a legal interpreter to resolve terminological issues.

Evaluate

This argument relies on an Analogy, signified by "in the same way". The author is trying to present chemists' using the periodic table as analogous to a lawyer or other legal interpreter's using a dictionary.

Whenever we're trying to weaken an argument based on an analogy, our primary thought is,

The periodic table is a tool used specifically by chemists. It contains information, such as atomic mass and number of electrons, that chemists use in their professional field.

Meanwhile, a dictionary is not a tool specifically for lawyers. So is it just as useful as a professional tool? Are ordinary definitions of words the same as legal definitions of words?

I'm guessing that if I looked up the word corporation in the dictionary, I wouldn't see any part of the definition refer to corporations "as people", yet in American law (thanks to Citizens v. United), the legal definition of corporation involves treating it like a person.

Goal

So let's look for something pointing out a salient difference between using an ordinary dictionary to interpret law and using a periodic table to do chemistry.

We want an answer that helps us argue that it wouldn't be a good idea for a law professional to use an ordinary dictionary to interpret law.

13.

Which one of the following, if true, most seriously weakens the argument?

The periodic table lists the
Weak Impact
This does point out some differences between the periodic table and an ordinary dictionary, and it does make the ordinary dictionary potentially seem less useful (because its organizational hierarchy isn't as rich in meaning). But it's a pretty mild attack. In order to argue that we can't use an ordinary dictionary to interpret law, we need to be able to say "you get bad information --- what it will tell you about a word like corporation isn't the legal meaning of that word". This is just saying that a dictionary doesn't do much to group words together into families that reflect relationships.
4% picked this
Correct
There is wide agreement about
Why this is right
This points to a difference between dictionaries and periodic tables, and the difference sounds meaningful when it comes to whether a legal interpreter should use an ordinary dictionary As the argument laid out the comparison, it says: Periodic table is 1. convenient source 2. agreed-upon background info 3. can be usefully applied to a chemistry problem Were we ever told that an ordinary dictionary was a convenient source of agreed-upon background info that can be usefully applied to a legal problem? No, and this answer is blowing up that assumed comparison. The periodic table is a standardized set of info that is widely agreed upon. But depending on which ordinary dictionary you're using, you might get a definition of a word that is not widely agreed upon and that is likely to impact the legal interpretation.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
88% picked this
The use of a periodic
No Impact
This points to a difference, but not a meaningful one. We don't care when, in history, these things were invented. We only care if presently an ordinary dictionary is as useful to a legal interpreter as a periodic table is to a chemist. Not to mention, since ordinary dictionaries have the greater longevity in this answer choice, the comparison is somewhat flattering to ordinary dictionaries, which would be the opposite of our purposes.
0% picked this
The periodic table contains only
No Impact
This shows us a difference, but not a meaningful one. No one is expecting anyone to memorize the periodic table or an ordinary dictionary, so how easily each thing is to memorize is irrelevant. Both of them are reference materials, and we judge their usefulness primarily on whether they allow us to look up accurate info.
1% picked this
The periodic table is used
No Impact
Like all the other answers, this did provide a distinction between the periodic table and ordinary dictionaries. But like the three other wrong answers, that distinction isn't one that gives us way to tell legal interpreters that they shouldn't use an ordinary dictionary. This problem essentially forced us to think about which distinction was most useful for arguing that "a legal interpreter shouldn't use an ordinary dictionary". Hey, lawyers, you shouldn't use an ordinary dictionary to resolve a terminological issue. After all, ... (A) they're organized alphabetically (B) depending on your dictionary you could get a definition that isn't agreed upon and likely is relevant to the legal interpretation (C) they were invented earlier than periodic tables were (D) they can't be memorized (E) they are used by non-legal professionals
6% picked this

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