Self-study
Political scientist: Support All governments worthy of respect allow their citizens to dissent from governmental policies. ██ ██████████ ██████ ██ ███████ ██████ ██████████ ████████████ ████ ███ ██████████ ████ ████████ ██████████ ███████ █████████ ██ ███ █████████
Method of Reasoning
As shown below, the political scientist provides two conditional facts as premises:
If a government is worthy of respect, it allows dissent.
If a government is worthy of respect, it protects minorities.
Based on these conditions, the political scientist concludes that all governments that protect minorities allow dissent.
Identify and Describe Flaw
This is an invalid argument form! Just because one subset of governments (the set of governments that are worthy of respect) both allow dissent and protect minorities, does not mean that every government that protects minorities must also allow dissent. Maybe there are some unrespectable governments that protect minorities but prohibit dissent!
19.
The flawed pattern of reasoning ██ █████ ███ ██ ███ █████████ ████ ███████ █████████ ████ ██ ███ █████████ ███████████ █████████
a
Politicians are admirable ██ ████ ███ ███ █████████ ██ █████ ████ █████ █████ █████ ███ ██████████ ██ ███████████ ███ █████████ ██████ ███ █████████ ██ █████ ███ ████████████ ██ █████ ██ ███ ██████ ██ █ █████ ███████ ███████████ ███ ████ ███ ███████ ███ █████████ ██ █████ ████ █████ █████ █████ ████
Wrong flaw. Ignoring the interests of your constituents is hardly acting in the interest of those you serve! But this isn’t the same flaw we see in the stimulus or the same argument structure: the premises are not two conditional claims with the same sufficient condition here, as they are in the stiumuls.
b
All jazz musicians ███ ███████ ██ ███████████ ███ ██ ████ ████████ ██ █████████ ██ ███████ ██████ █████████ ███ █████████ ███ ███ ████ █████ ███ ██████████
As shown below, this argument gives two conditional facts as premises:
If a person is a jazz musician, she can improvise.
If a person is a jazz musician, she can read music.
Based on these conditions, the argument concludes that all musicians who can read music can improvise. But just because one subset of musicians (jazz musicians) can both read music and improvise, does not mean that every musician that reads music can improvise. This is the same argument structure and flaw from the stimulus!
c
Ecosystems with cool, ███ ████████ ███ █████████ ██ █████ ████████ ██ ██████████ █████████ ██ █████ ███████ ████ ████████ ███ ██████ █████ █████ ████ ██████████ ████ ██ ███ ████ █████ ███ ████████ ████ ████████ ███ ██████ █████ █████
Wrong flaw. This argument makes a negation mistake. We could conclude that ecosystems with cool, dry climates lack abundant and varied plants, but (C) negates these terms, concluding that ecosystems without cool, dry climates have abundant and varied plants. That isn’t valid, but it’s not the flaw from the stimulus. The stimulus doesn’t make a negation error, and the structure is different: (C)’s premises are a conditional chain, while the stimulus’ premises are two conditional claims that share a sufficient condition.
d
Some intellectuals are ███ ████████ ███████ ███ ██ ████████████ ██ █ ████████████ ████████ █████████ ███ ████████████ ███████ ██ ████████ ███████
Wrong flaw. Like the stimulus, (D)’s premises are two conditional claims sharing a sufficient condition, and like the stimulus, its conclusion invalidly links the necessary conditions from the premises. Unlike the stimulus, however, one of (D)’s premises involves a “some” quantifier, which gives the argument a fundamentally different structure.
e
First-person narratives reveal ███ ████████ ██ ███ ████████ ███ ███████ █████ ██ ███ █████ ███████████ ████ ████████████ ██████████ ██████ ███ ███████ ██ █████ ██████████ ████ █████ ████ ████ ██ ██████ ███ ███████████ ███████ ████████ ██████ ██ ███████ ██ ███ █████ ███████
Wrong flaw. This argument relies on a false dichotomy (that the only possible narrative forms are first and third person). But this isn’t the same flaw or argument structure from the stimulus: the stimulus does not use a false dichotomy, (E) has a “some” quantifier, and (E) does not take the same argument structure.