Asking the Right Questions, A Guide to Critical Thinking, 8th Ed

What Are the Descriptive Assumptions? 73
This model of car
performed well
often.
• c«,v, .,«„. * n „«~K ! • The "driving" of the
• From year to year, • : . r ..
A • car models have - j. I
person 9 lvin 9 the
+
*
C n C 2n,Sl! î + • recommendation is
consistent quality. . .. .. .. ...
• • I identical to your driving.
•••••••••••••• ••••••••••••••••
T
This car is
dependable.
for a term that has multiple possible meanings. Let's see what this process
looks like in argument form:
Once you have identified the connecting assumptions, you have answered
the question, "On what basis can that conclusion be drawn from that reason?"
The next natural step is to ask, "Is there any basis for accepting the assumptions?"
If not, then, for you, the reason fails to provide support for the conclusion. If so,
then the reason provides logical support for the conclusion. Thus, you can say
reasoning is sound when you have identified connecting assumptions and you
have good reason to believe those assumptions.
Attention: A descriptive assumption is an unstated belief about how the
world was, is, or will become.
When you identify assumptions, you identify ideas the communicator
needs to take for granted so that the reason is supportive of the conclusion.
Because writers and speakers frequently are not aware of their own assumptions,
their conscious beliefs may be quite different from the ideas you identify
as implicit assumptions. When you then make the hidden connecting tissue of
an argument visible, you also contribute to their understanding of their own
argument and may thereby guide them to better beliefs and decisions.
USING THIS CRITICAL QUESTION
After you have found descriptive assumptions, you want to think about
whether there is a strong basis for accepting them. It is certainly fair for you
to expect the person making the argument to provide you with some justification
for why you should accept these particular assumptions. Finally, if the
assumption is not supported and you find it questionable, you are behaving
responsibly when you decide not to buy the argument. Your point in rejecting