-2) Explain the difference (if any) in meaning between: a)  P if Q          b)  P because Q
 

-1) Explain, in one good sentence, what it means to say that an argument is valid:
 

0) Explain, in one good sentence, what it means to say that an argument is strong:
 

1)  T or F.  An argument with a true reasons and a false conclusion must be invalid.

2)  T or F.  It is possible for a valid argument to have a false conclusion.

3)  T or F.  It is not possible for two false statements to be inconsistent with each other.

4)  T or F.  An valid argument with a false conclusion must have at least one false reason.

5)  T or F.   Valid arguments always have true conclusions.

6)  T or F.  Valid arguments always have true reasons.

7)  T or F.  True statements are always consistent with each other.

Put the letter (A, B, C, D) for the correct answer in the blank.  A = true reasons, valid argument.   B = true reasons, invalid argument.    C = at least one false reason, valid argument.  D = at least one false reason, invalid argument.

___ 8)   Giraffes are taller than human babies, and human babies are taller than ants.  Thus giraffes are taller than ants.

___  9)   If the moon is made of blue cheese then it is edible.  And the moon is in fact edible.  Therefore, the moon is made of blue cheese.

___  10)  Elephants are bigger than lions, and elephants are bigger than chickens.  So, lions are bigger than chickens.

___ 11)     Birds are two-legged, and all two-legged things have feathers.  It follows that birds have feathers.

Just do diagrams for these two arguments (skeletons are optional).   Put parentheses and numbers in the text so that it is clear which particular statement each number of your diagram stands for!

12)  There are over 12 million pot smokers in the U.S. today, even though smoking

pot is illegal just about everywhere in the country.  Thus, more than 12 million people

regularly decide, in effect, that it is better to break the law than not to.  It is simply

impossible to have fair enforcement of laws which are broken regularly by that many

citizens.  And laws which can't be properly enforced ought to be repealed, because

unenforced laws create a general disrespect for other laws, and such a situation is

contrary to the best interests of society.  These considerations show why the use of

marijuana ought to be decriminalized.
 
 

13)  In recent years the sense of responsibility to society and to conduct oneself honestly

has declined considerably.  It is being replaced by a selfish, egocentric cult of "everybody

for himself".  The reasons for this increase of dishonesty and self-centeredness are

obvious.  One is that corruption in high places has a demoralizing effect on those lower

down.  It is well-known that some high government officials have submitted fraudulent

income tax returns.  Because of this, ordinary citizens are sorely tempted to do the same

thing.  In addition, we have in recent years seen large increases in government spending,

and these billions of dollars are spent with little careful supervision over where they go.

Thus it is easy for government officials and others to misuse the money.  And finally, our

criminal justice system is so overloaded that most offenders don't get caught, and those

that do get off with light penalties.  This also undermines the motivation to act responsibly

and unselfishly.
 

Fallacies mostly.   For each of these, do numbers and a diagram, then make appropriate evaluative comments about the strengths or weaknesses of the arguments.  Explain any fallacies that are present.  If you see no fallacious reasoning (i.e. if the reasoning is valid, or invalid but nonetheless strong) then write “no fallacy” by the diagram.   If one of the seven argument forms is present, identify it.  If you see a flaw in the argument but it doesn’t seem to “fit” any fallacy we have covered, then explain in your own words what the flaw(s) is (are).

14)  Most people trust their doctor's medical judgment; but they shouldn't, because

doctors very often make serious mistakes.  Why, just last week I heard about a patient

who underwent treatment for a problem that it turned out she didn't really have! And

that's the second case of  misdiagnosis I've heard about this year.
 
 

15)  That the human soul is immortal is easily shown.  Consider the following points.

Anything that dies, decomposes.  Anything that decomposes must be a physical object.

But the human soul is not a physical object.  Hence the human soul cannot die.
 
 

16) The Marxists say that all political, social, and cultural changes are the results of

economic changes. History clearly supports their view, because any political, social, or

cultural change has always been preceded by some economic change.
 
 

17) A tourist agency ought never to be held liable for damages when someone on a

tour it is sponsoring is injured in an accident. This is because it would obviously be

ridiculous for the owner of a tourist agency to be liable for paying damages to a client

who was injured by slipping on a banana peel in the middle of Rome!
 
 

18)  From the latest Pentagon intelligence reports it is quite clear that the Chinese are

well-informed about Russian military movements.  So we can be sure that China would

station several additional divisions along their border with Russia if Russian strength on

the other side had significantly increased.  But there have been no such shifts of Chinese

troops.  Therefore the Russians have not been beefing up their forces along that border.

19)  If a candidate supports increased government programs for our citizens, and higher

taxes to pay for those programs, then the people who are fed up with high taxes will vote

against him.  But if he doesn't, then all the people who think that they really deserve

more services from the government will vote against him.  A candidate can't come out

ahead either way.  Thus, you see, there is no position which a candidate can take on taxes

which will be able to receive widespread support in an election.
 
 

20)  Since all people are mortal, the human race will someday come to an end.
 
 

21)  In this day and age medical progress is highly respected and we are inclined to

overlook the fact that medicine can produce diseases as well as cure them.  Disorders

which are caused by medical treatment are called "iatrogenic", and we can show that

iatrogenic illness is a major problem today by considering the things that have happened

with heart disease.  Several generations ago there was no special emphasis on heart

disease research and treatment, and in those days heart disease was not nearly the

problem it is today.  Then it was nowhere near to being the leading cause of death -

but today it is.  We all know that funds devoted to heart disease research and treatment

have multiplied at a rapid rate over the same period of time, and new methods of

treatment such as bypass surgery and intensive care units have been introduced.  Thus

the increase in heart disease has paralleled the increase in research and in new treatment

methods.  The appropriate conclusion to reach on the basis of these trends is that the

modern epidemic of heart disease is largely iatrogenic.