Daily Drills 42 - Section 42 - Question 1

The conclusion above is properly drawn from the premises given if which one of the following is true?

kmstone2 March 10, 2019

Deciding between strengthen with necessary premise vs. Sufficient premise

I am struggling with deciphering between when a strengthen question is referring to the sufficient condition or the necessary condition. Is there a method to distinguishing between the two?

Reply
Create a free account to read and take part in forum discussions.

Already have an account? log in

Ravi March 12, 2019

@kmstone2,

Happy to help.

The two question types you're referring to are strengthen with a
necessary premise and strengthen with a sufficient premise. Let's take
a look at how they differ.

1) strengthen with a necessary premise questions

These questions typically say things like

Which one of the following is an assumption on which the argument depends?

Which one of the following is an assumption required by the
editorial's argument?

The consumer's argument relies on the assumption that

Which one of the following is an assumption on which the argument depends?

Which one of the following is an assumption required by the
researcher's argument?

The key giveaway in these question stems that tell us they're
strengthen with a necessary premise questions is that they all contain
wording that tells us that we're looking for an assumption that the
argument NEEDS/REQUIRES/HAS TO HAVE in order for it to have any chance
at holding up.

Necessary premises are premises that must be true in order for the
argument to hold. In other words, if a necessary premise is false,
then the argument falls apart.

2) strengthen with a sufficient premise questions

These question types typically say things like

Which one of the following, if assumed, enables the psychologist's
conclusion to be properly drawn?

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

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

Which one of the following, if assumed, enables the essayist's
conclusion to be properly drawn?

The conclusion of the criminologist's argument is properly inferred if
which one of the following is assumed?

The key giveaway in these question stems that tell us they're
strengthen with a sufficient premise questions is that they all
contain language that tells us that we're looking for an assumption
that, if true, ENABLES THE CONCLUSION TO BE DRAWN/JUSTIFIES THE
ARGUMENT, etc. In other words, we're looking for an assumption that,
if true, makes the argument valid.

Sufficient premises are premises that, if we add them to the argument,
automatically make the argument valid.

To recap, think of necessary premises as premises that, if false, make
the argument lose. Think of sufficient premises as premises that, if
true, make the argument win (valid).

Does this help? Let us know if you have any more questions!