Inductive Reasoning
The Missing Premise or Conclusion?
• I don’t see how
Mike could have
high blood
pressure; he
jogs, what, ten
miles a day?
The Missing Premise or Conclusion?
• Most people who
drive that kind of
car have money to
burn, so I imagine
Rico is pretty well
off.
The Missing Premise or Conclusion?
• Andy belongs to
the NRA. He’s
probably a
republican.
The Missing Premise or Conclusion?
• Kym is telling the
truth; nine times out
of ten, when
someone says she
cares for what people
think and feel, she’s
telling the truth.
ID the Sample, Population, & Attribute of Interest
• Most of my
professors at CR
wear glasses; it’s a
good bet that
professors at all
colleges wear
glasses.
ID the Sample, Population, & Attribute of Interest
• CR students are
stylish! Did you see
the guys at that
party on Saturday?
1-5…How Well Does the Sample Represent the
Population: 1= very well; 5 very poorly
• The coffee in that pot is awful. I just had a cup.
• The coffee at Adele’s is awful. I just had a cup.
• Starbucks coffee is strong. I just had a cup.
1-5…How Well Does the Sample Represent the
Population: 1= very well; 5 very poorly
• Sherry doesn’t write
very well, based on
how poorly she did on
this 5-page paper.
• Sherry writes very
well, based on how
well she did on this 5page paper.
1-5…How Well Does the Sample Represent the
Population: 1= very well; 5 very poorly
• Salesperson: As
you can see from
these two
pictures, HDTV is
much sharper
than regular TV.
Claim: “Most CR students I’ve met believe in God.
Therefore, most CR students believe in God.”
• Students you met were leaving a local church after Sunday
services.
• Students you met were all first-year students.
• Students you met were all philosophy majors.
• Students you met were selected by picking every tenth name
on an alphabetical list of students’ names.
• Students were all students who responded to a questionnaire
titled “Survey of Student Religious Beliefs.”
• Students were randomly selected from a list of registered
automobile owners.
Analogy or Argument from Analogy?
• I love washing
dishes like I love
cleaning the
bathroom.
Analogy or Argument from Analogy?
• Too much sun will
make your face
leathery. I suppose
it will have the
same effect on
your hands.
Analogy or Argument from Analogy?
• Hammers can be used
as deadly weapons,
and guns can be used
as deadly weapons. It
would be dumb to
regulate the sale of
hammers, so it’s also
dumb to regulate the
sale of hammers.
Rank from Most Similar to Most Dissimilar
•
•
•
•
•
Football and bowling.
Football and golf.
Football and basketball.
Football and chess.
Football and tennis.
Rank from Most Similar to Most Dissimilar
• Rock concert and bluegrass
concert.
• Watching Lady Gaga on YouTube
and seeing her in concert.
• Going to ballet and watching
Lady Gaga.
• Listening to classical music and
reading poetry.
• Seeing Lady Gaga in concert and
watching 4th of July fireworks
show.
Evaluate the Strength of the Argument
• Ericka was good as
the manager of
Sushi Spot, so she’ll
probably be good as
the manager of
Napa Auto Parts.
Evaluate the Strength of the Argument
• LaRissa is great at
bowling. She’d
probably be great
at poker.
• LaRissa is great at
bowling. She’d
probably be great
at croquet.
Evaluate the Strength of the Argument
• Joe shows up to
work on time.
I’ll bet he pays
his rent on time.
Evaluate the Argument
• “The proponents of school vouchers say, in
essence, that if competition produces
excellences in other fields—consumer
products, athletics, and higher education, to
name but three—it would be healthy for
schools as well. Their logic is difficult to
refute.”
– Dan Walters, columnist, Sacramento Bee
Slanted?
• Was British Petroleum
(BP) slow to respond to
the gulf oil spill
because they didn’t
care or because they
hadn’t adequately
prepared for drilling in
the deep water?
Slanted?
• Do you agree or
disagree that
immigration laws
should be more
vigorously
enforced?
Slanted?
• Polls indicate that most
Americans are satisfied
with their health care.
Do you agree that
health care reform is
needed?
Slanted?
• When framing new
laws, should
legislators be guided
by Judeo-Christian
principles or only by
secular
considerations?
Exercise 10-30
1. My cousin uses a
Dodge truck on his
ranch; it has over
300,000 miles on the
original engine.
Obviously, Dodge really
does build tough
trucks.
2. Things are getting better all the time.
3. I ordered a packet of
California
watermelon seeds
from Hansen Seed
Company last year,
and they germinated
like crazy. I expect
the seeds I ordered
this year to sprout,
too. Of course, it’s a
little colder up here
in Canada than it was
in El Paso.
4. Poker? Nah, I
don’t like card
games.
5. Drug abuse among
pro athletes is
unquestionably a
serious and
widespread problem.
Why, last week three
players from just one
team said they used
HGH!
6. Orange cats are easy to train. I had one
once—Gross Kitty we called him—and you
could teach that cat to ski if you wanted to.
7. You’re gonna take a course from Professor
Toadstool? You should talk to Stan and Charlie.
They both think she’s awful. She flunked both
of them.
8. Most Americans
favor a national
lottery to reduce the
federal debt, judging
from the poll taken in
Las Vegas where
about 80% said they
liked the idea.
9. Young people
these days are too
easily distracted
by things. Just
look at the kids in
this class.
10. Most Ohio residents
are worried about air
quality. In a survey
taken in Cleveland,
more than half the
respondents identified
air pollution as the
most significant
environmental hazard.