Logic Final
What is an argument?
A number of statements or propositions where one is a conclusion and the others are premises meant to support the conclusion.
Inference is:
A way of learning about the world by recognizing the connection between things we know and other things to which they are conceptually tied.
Testimony is:
A way to learn about the world by others' statements.
Perception is:
A way to learn about the world through direct experience.
It's true, Ms. Zerkle will be accepted into law school only if she has excellent grades. But I'm telling you, you should see her transcript; she's made straight A's for the past two years. So don't worry about her getting into law school. She'll be accepted without a doubt.
Affirming the consequent
Jamal is a devout Muslim only if he follows the Sharia law, and I know for a fact that he follows it to the letter. So he is a devout Muslim.
Affirming the consequent
What version below is the best way to render "Amazon warriors are fierce" in standard form?
All Amazon warriors are fierce warriors
What is the contradictory of "some S are not P".
All S are P.
Anything that's an alligator is a reptile.
All alligators are reptiles.
Translate "Foolish is the person who lies to his loved ones" into standard form.
All people who lie to their loved ones are foolish.
Which of the following is the best definition of validity?
An argument is valid if and only if the truth of its premises guarantees the truth of the conclusion.
What determines factual strength?
An argument's content
What determines logical strength?
An argument's form
Jamal keeps his word, so he is a man of good character.
Anyone who keeps his or her word is a person of good character.
Avril is a conservative because she voted against gun control.
Anyone who votes against gun control is a conservative.
Wife: Don't you agree that my hair looks nice like this? (If you disagree, you will find yourself divorced). Husband: Yep, looks great.
Appeal to force
The president is a crook. -Why do you say that? Well, nobody has proven otherwise.
Appeal to ignorance
You should buy your books from Amazon.com. -Why? Because most people do it.
Appeal to the Majority
What kind of argument is the following: "Since most of the people from this region smoke cigarettes, I bet that guy who lives here also smokes."
Argument from Sample
What is distributed in "No person can thrive without support"?
Both
What is distributed in the following statement? No students left home early.
Both
If the Lambda Xi's continue to throw those open parties, they're going to get cited by the police. So if they continue the parties, they'll get decertified by the university because the university will certainly decertify them if they're cited by the police.
Chain argument
If the carburetor is clogged, the engine will run lean, and running lean will lead to overheating. So overheating can result if the carburetor is clogged up.
Chain argument
Why do you think that he will be a good leader -because he is trustworthy How do you know that? -he told us in his many speeches.
Circular reasoning
Dogs are smarter than cats because it is easier to train them.
Conclusion: Dogs are smarter than cats
When blue jays are breeding, they become aggressive. Consequently, scrub jays, which are very similar to blue jays, can also be expected to be aggressive when they're breeding.
Conclusion: Scrub jays can be expected to be aggressive when they're breeding
The darned engine pings every time I use the regular unleaded gasoline, but it doesn't do it with the super. I'd bet that there is a difference in the octane ratings between the two despite what my mechanic says.
Conclusion: There is a difference in the octane ratings between the two grades of gasoline
"No person is nice" and "some people are nice" are:
Contradictories
All of my books are used and Some of my books are not used are:
Contradictories
Mr. Stooler will never make it into the state police. They have a weight limit, and he's over it.
Premise: The state police have a weight limit, and Mr. Stooler is over it Conclusion: Mr. Stooler will never make it into the state police
"There are more injuries in professional football today than there were twenty years ago," he reasoned. "And if there are more injuries, then today's players suffer higher risks. And if they suffer higher risks, then they should be paid more. Consequently, I think today's players should be paid more," he concluded.
Premise: There are more injuries in professional football today than there were twenty years ago Premise: If there are more injuries, then today's prlayes suffer higher risks Premise: If today's players suffer higher risks, they should be paid more Conclusion: They should be paid more
I guess Thork doesn't have a thing to do. Why else would he waste his time watching daytime TV?
Premise: Thork wastes his time watching daytime TV Conclusion: Thork doesn't have a thing to do
What is critical thinking?
Reflecting on one's own beliefs and trying to be objective about them.
"Going shopping is annoying. It is tons of trouble to find parking, and then you have to deal with salespeople and other customers who want to get the same things that you do." What is the conclusion of the above argument?
Shopping is annoying.
I don't think you should drink coffee. If you drink coffee, you get excited. Then, you will do something rash, like running out in the middle of traffic. Then you will die. So just don't drink it.
Slippery slope.
What is the correct symbolization of the following argument? Some students are mean No mean people have friends So, some students don't have friends
Some S are M No M are P So some S are not P
If "All people are nice" is false, what must be true?
Some people are not nice.
"If p, then q" and "If not-q, then not-p" are equivalent propositions.
T
A conditional is false if and only if its antecedent is true and its consequent is false.
T
A sound argument is a valid one with true premises.
T
An important aspect of logic is determining what beliefs are justified and what beliefs are not justified
T
Deductive arguments are sometimes valid and sometimes invalid.
T
If a valid argument has a false conclusion, then it must have at least one false premise.
T
If a valid argument has a false conclusion, then not all its premises can be true.
T
If an argument is sound, it must be valid as well.
T
In "p only if q", the variable q stands for a necessary condition.
T
Inductive arguments are always invalid.
T
Validity is a property of deductive arguments only.
T
if p, then q = p is sufficient for q.
T
if p, then q = q is necessary for p
T
The word "if" when used alone introduces which of the following?
The antecedent of a conditional
necessary conditions are always on what side of a conditional
The consequent (the "then" side)
The phrase "only if" introduces which of the following?
The consequent of a conditional
What is the best way to classify the following argument: 1. If Michael Jordan were president, the United Nations would agree to do whatever America wants. 2. Michael Jordan is the president. 3. Therefore, the United Nations will agree to do whatever America wants.
Valid
Iraq posed a threat to us, so we had a right to invade it.
We have a right to invade any country that poses a threat to us.
What would make x a necessary condition for y?
Whenever y is the case, x must also be the case
Which of these normally would call for a balance of considerations argument?
Whether swimming is better for you than jogging
Which of these normally would call for a balance of considerations argument?
Whether to go with AT&T or Verizon
Is the following argument valid? 1. If p, then (q and r) 2. not-r 3 not-p
Yes
Mike: President Obama is a Communist, plain and simple. Lydia: How do you know that? Mike: Everybody knows that. Most polls show that 60% of the people asked claim that he's a communist. What did Mike do?
appeal to the majority
Which of the following is not a kind of inductive argument?
argument by expert opinion
What kind of argument is the following? About three-quarters of Italians drink wine with dinner. That guy is italian. So, he probably drinks wine with dinner.
argument from sample
What kind of argument is the following? I have eaten at that restaurant 6 times, and every time the food is horrible. Let's face it, the food is just bad there.
argument from sample
Ian: I support the Tea Party because they are right about the relationship between the government and private individuals. I think that it isn't the role of government redistribute people's wealth. Rather, its job is to protect individual rights. We should encourage private individuals to give in charity, but not force them too through taxation. Cathy: Well, that can't be right, since the Tea Party is full of racists and homophobes. What did Cathy do?
attacking the person
Sarah Palin says that the only way to fix politics in Washington is to remove the power of lobbyists to influence laws. -Look man, Sarah Palin is an idiot, so that can't be right.
attacking the person
The proposition "p or q" is false if and only if
both p and q are false
The proposition "p and q" is true if and only if
both p and q are true
Meghan: Like I said, Jason, it is wrong for private citizens to own firearms. Jason: Why? Meghan: Because it's not right for them to own guns. What is Meghan doing?
circular reasoning
Which of the following is not an inductive argument type we have discussed:
circular reasoning
The two things related by "and" are called
conjuncts
"Everybody likes ice cream" and "nobody likes ice cream" are
contraries
"Sheila's clarinet is French. It's a Leblanc, and all Leblanc instruments are made in France." This argument is best taken as
deductive
What kind of argument is the following? That animal is a shark. All sharks must live in salt water. So that animal must live in salt water.
deductive argument
What kind of argument is the following? You can either swim or sink. But you aren't sinking. So you must be swimming.
deductive argument
if p, then q not-p Therefore, not-q What is this argument
denying the antecedent
In "p or r", p and r are called
disjuncts
Cathy: Ian accused president Obama of not really being a US citizen. Can you believe that? Matthew: He did? What did he say? Cathy: He said Obama's attitudes are un-American. What is Cathy doing?
equivocation
Ed: I think that Laura is a horrible person. Ian: Well that's a pretty strong claim. What is your evidence? Ed: I overheard her saying that she hopes the Patriots kill the Jets. Only horrible people wish death upon others. What did Ed do?
equivocation
Jonathan: I think I should get a divorce. Matthew: Why? Jonathan: Because my wife and I get into fights sometimes, and you can either keep getting into fights or just get a divorce. What did Jonathan do?
false dilemma
Why are you out here on the street protesting? -Well as I see it, you are either against the wealthy or a slave to the wealthy, and I am no damn slave.
false dilemma
What is distributed in the statement "Some baseball players are not fast"?
fast people
What is distributed in the following statement? Some people are not good athletes
good athletes
Symbolize the following proposition (use the first letter of each phrase or word for the variable) I will join the team if you play baseball or football.
if (b or f), then j
Please translate the following into standard form: p unless q.
if not-q, then p
what makes x a sufficient condition for y
if x is true, then y must also be true
In the proposition "he must be a hunter or a gun collector", what kind of "or" is being used?
inclusive
"The ensemble played an encore at last year's concert, and I'm pretty sure they played one the year before as well. So they will most likely play an encore at this year's concert." This argument is best taken as
inductive
"The ensemble played an encore at last year's concert, and I'm pretty sure they played one the year before as well. So they will most likely play an encore at this year's concert." This argument is best taken as
inductive.
What kind of argument is the following? The thieves broke into the house, but didn't steal anything of value. They were probably looking for information, not valuables.
inference to the best explanation
"You'll get an A in the class," she predicted. "What makes you say that?" he asked. "Because," she said, "if you get an A, then you're smart, and you are smart." is the argument:
invalid
Bob has a green truck. And some green trucks are faster than jeeps. So Bob has a vehicle that is faster than a jeep.
invalid
If p, then q q Therefore, p This argument is
invalid
Is this valid or invalid? p or q p Therefore, not-q
invalid
Some M are S Some M are P So, Some S are P
invalid
a or b b Therefore not-a
invalid
if p, then q not-p Therefore not-q This argument is:
invalid
The proposition "if p, then q" is false if and only if:
it is possible for p to be true while q is false
When succesful, inductive arguments
make their conclusions more likely.
If p, then q not-q Therefore, not-p What is this argument?
modus tollens
If we know that a valid argument has true premises, then the argument
must be sound
In the conditional "if p, then q" q is
necessary for p
What is distributed in the statement "Some people are lucky"?
neither
Is the following argument valid: 1. If (p and q), then r 2. p 3. Therefore, r
no
Gal: I think that the Koran is the word of God. Matthew: Really? Why? Gal: Because when I read it prayerfully and with an open heart, I feel the presence of God in my life. What is Gal doing?
no fallacy
Mike: I think that we never went to the moon. It was all fabricated. Lydia: how to you justify that claim? Mike: This is what is says on conspiracytheories.com Lydia: But that website has been discredited many times. Most of its claims are demonstrably false. What is Lydia doing?
no fallacy
Mira: I think that gay marriage is morally acceptable and should be legal. Ken: Why? Mira: Because the role of the government is to only step in and control individual citizens when they do something that could harm someone else, and preventing a relationship between two consenting adults is not the government's business. What did Mira do?
no fallacy
Robin: I think that Salvador Dali is overrated as an artist. Time and time again, when the Association of Art Historians publish their research on 20th century art, he is found to be far behind other artists who are less well known. What did Robin do?
no fallacy
Tristan: If you get too close to the dog it will bite you, so stay away from it. Sharmane: But I love dogs. Tristan: look, you will get hurt real bad if you get too close. What did Tristan do?
no fallacy
Which of the following is NOT an appropriate translation of "if p, then q".
p is necessary for q
What is distributed in the following: A penny saved is a penny earned
pennies that are saved
When successful, deductive arguments
prove their conclusions.
What is distributed in the following: Some people never quit
quitters
Which of the following is NOT a conclusion indicator
since
When you are nice to children, they won't respect your authority. And if they don't respect your authority, they will do whatever they want. Eventually, they will end up committing crimes because they just don't care. So don't be nice to children.
slippery slope
in the conditional "if p, then q" p is
sufficient for q
Is the following argument valid or invalid? If you value your feet, you won't mow the lawn in your bare feet. Therefore, since you do mow the lawn in your bare feet, we can conclude that you don't value your feet.
valid
Jim is going to go on a walk or work out today. But he won't go for a walk, since it is raining. So, he'll just work out.
valid
a or b not-b Therefore, a
valid
In order to be sound, an argument must be
valid and have true premises.
What is an argument's content?
what the premises actually say, which can be true or false
Is the following argument valid? 1. p or q 2. not-p 3 Therefore, q
yes
Is the following argument valid? a or (b and c) not-c Therefore, a
yes
Please translate the following into standard form: You can have dessert unless you aren't hungry.
If you're hungry, you can have desert.
Joel will automatically be accepted provided he got his forms in on time. Unfortunately, he did not get his forms in on time; so he won't be automatically accepted.
Modus tollens
I think that the wealthy have a moral obligation to help others, and the government is meant to help us live morally. Therefore, it is okay for the government to take some of their wealth to help those who are less fortunate.
No fallacy
Translate "No times that she suggests will work for our meeting".
No times she suggests are times that will work for out meeting.
The Lakers almost didn't beat the Kings. They'll never get past Dallas.
Premise: The Lakers almost didn't beat the Kings Conclusion: They'll never get past Dallas
Let's see . . . because the clunk comes only when I pedal, the problem must be in the chain, the crank, or the pedals.
Premise: The clunk comes only when I pedal Conclusion: The problem is in the chain, the crank, or the pedals
Mr. Stooler will never make it into the state police. They have a weight limit, and he's over it.
Premise: The state police have a weight limit, and Mr. Stooler is over it Conclusion: Mr. Stooler will never make it into the state police
Caleb is going on a road trip. But people on the road trip can't visit India. So Caleb will not go to India.
valid
What is the best symbolization of the following argument? (c = we care about the environment; p = there will be severe problems down the road; s = our children will suffer.) 1. Unless we care about the environment, then there will be severe problems down the road. 2. If there are severe problems down the road, then our children will suffer. 3. But our children shouldn't suffer. 4. Therefore, we should care about the environment.
1. If not-c, then p 2. If p then s 3. not-s 4. Therefore, c
Represent the following argument with variables, (g = give someone a greeting card; c = care about him). 1. If you give someone a greeting card, then you care about him. 2. She doesn't care about him. 3. Therefore, she doesn't give him a greeting card.
1. if g, then c 2. not-c 3 Therefore, not-g
What kind of a proposition is "A well-fed person is a happy person"?
A
What kind of statement is the following: That guy is a loser.
A
What kind of statement is the following: Everyone I know is going to vote for Hillary.
A
What is the best definition of an argument below?
A conclusion which is supported by premises.
What is the problem with the following argument? The problem with the death penalty is that we use it to often. Typically, people who get the death penalty are people who break marijuana laws or forget to pay their taxes. And these aren't things we should kill people over. Therefore, the way we apply the death penalty in this country is wrong.
A lack of factual strength
What statement below best expresses the following claim: "When people smoke in crowded places, they don't care about the health of those around them."
If people care about the health of those around them, then they don't smoke in crowded places.
What translation below is equivalent to: "She will never be happy if she never cares about other people."
If she is happy, then she cares about other people.
If the Saints win the Super Bowl again, it will be poetic justice for New Orleans, the country's most bad-luck city in recent years. Unfortunately, the Saints have no chance to repeat the win, so there'll be no poetic justice this year for "N'awlins."
Denying the antecedent
What kind of a statement is "Tall people are not good at being jockeys"?
E
What kind of statement is "No one who lives here is difficult to be around"?
E
What kind of statement is the following: No carpenters are bad at math.
E
Jim, you are so cruel to animals. -No I'm not, Nancy, I am an animal lover, since I really love fried chicken.
Equivocation
Which of the following is an A statement?
Everyone who meets Judy likes her.
What is the best way to put the following into standard form: the teapot on the stove is whistling
Everything in the class of the teapot on the stove is in the class of things that whistle
"Diane will be fine if her surgery goes well." In this sentence, "if her surgery goes well" is the consequent.
F
A conditional is an argument involving an antecedent and a consequent.
F
A valid argument cannot have any false premises.
F
A valid argument is also sound.
F
An argument is valid if the premises make the conclusion more likely.
F
An argument must have at least two premises.
F
Inductive arguments are sometimes valid and sometimes invalid.
F
Is the following claim true or false? Logic is something very personal. I have my logic and you have yours.
F
Some claims are valid while others are invalid.
F
Some inductive arguments are valid.
F
The best kind of argument from sample is a valid one.
F
The best kinds of arguments are true arguments.
F
The defining feature of a deductive argument is that, when successful, it makes its conclusion more likely.
F
The form of an argument is based on the truth of its premises.
F
What statement is equivalent to "Unless you take your vitamins, you won't grow big and strong."
If you don't take your vitamins, you won't grow big and strong.
Please translate the following into standard form: I will go to the party if you go.
If you go to the party, then I will go.
What is the appropriate translation of the following in standard form: "You are going to fail the class unless you stop goofing off."
If you goof off, then you will fail the class.
Why did you punch that guy? -Well, when somebody is rude to you you can either stand up to him or be a coward, and I am not a coward.
False alternative
Why do you think that this is the best cell phone on the market? -I saw a commercial where Tom Brady said it is the best one out there.
False authority
An argument's validity depends upon its:
Form
In the following argument: "I think people aren't compassionate enough. If they were, they'd give more to charity." What can we know about the second sentence?
Giving more to charity is implied by being compassionate enough.
What is logical strength?
How well an argument is structured.
What determines an argument's strength?
How well the premises support the conclusion
Try to symbolize the following sentence with variables and "or", "and", or "if. . . then". Use the first letter of the words below to stand for the entire word or phrase. "Whenever I am sad and drunk I call ex-girlfriends."
If (s and d), then c
Try to symbolize the following sentence with variables and "or", "and", or "if. . . then". Use the first letter of the words below to stand for the entire word or phrase. "Whenever I am sad or drunk I call ex-girlfriends and yell."
If (s or d), then (c and y)
Please translate the following into standard form: When it rains it pours.
If it rains, it pours.
What is the correct way to write "unless x, y" in standard form.
If not x, then y.
Translate the following propositions into symbolic notation (use the first letter of each phrase for its variable): Pete will visit the aquarium only if janet comes too.
If p, then j
Please translate the following into standard form: Whenever p happens, q happens.
If p, then q
Which of the following arguments is invalid:
If p, then q not-p Therefore, not-q
"She has a lot of books. She must be an avid reader or a book collector." What kind of "or" is being used?
Inclusive
What kind of argument is the following? This morning, when I looked at our garden, plant leaves and scraps of vegetables were scattered all around. I bet some rodents got in there last night and ate as much as they could.
Inference to the best explanation
What kind of argument is the following? "There are tons of people gathering together in the Park, and I hear music playing. There's probably a concert today.
Inference to the best explanation.
"You'll get an A in the class," she predicted. "What makes you say that?" he asked. "Because," she said, "if you get an A, then you're smart, and you are smart." is the argument:
Invalid
Alexander will finish his book by tomorrow afternoon only if he is an accomplished speed reader. Fortunately for him, he is quite accomplished at speed reading. Therefore, he will get his book finished by tomorrow afternoon. is the argument:
Invalid
Claims without supporting arguments are not convincing. And her claim isn't convincing. So it doesn't have a supporting argument.
Invalid
I think Ken will do well on the exam, since he rarely leaves his room, and people that do well on the exam rarely leave their rooms.
Invalid
If p, then q q Therefore, p This argument is
Invalid
Is this valid or not? Whenever she sings, it makes me happy. But I'm definitely not happy now, since she is not singing.
Invalid
No P is M No S are M So, All S are P
Invalid
The following valid or invalid: If your theory is correct, then light passing Jupiter will be bent. Light passing Jupiter is bent. Therefore, your theory is correct.
Invalid
For the statement "unless people can swim, they are not allowed on the cruise", what do we know about the proposition "they are not allowed on the cruise"?
It is a necessary condition of "people can't swim".
What is inference?
Knowing something by tracing it's connection with a sign or indicator.
What is wrong with this argument? She could be in her home, at the park, or in the office. But she's not at home, so she must be in the office.
Lack of logical strength
Which of these sentences is true?
Logic is an academic discipline that studies what makes certain beliefs justified or unjustified. Logic is an academic discipline that studies what makes arguments good or bad. Logic is an academic discipline that studies what makes arguments valid, invalid, sound or unsound. ALL of the above.
What is distributed in "Blessed are the Meek"?
Meek
There are Taliban in North Waziristan; if there are Taliban there, you can be sure they're in South Waziristan, too. So we have to believe there are Taliban in South Waziristan.
Modus ponens
If Sheila were ever to become a successful trader, she would have to develop a ruthless personality. But you know her; she could never be ruthless, even for a minute. So it's not going to be in her future to be a successful trader.
Modus tollens
Translate "Frank is not a good comedian" into standard form.
Nothing in the class of Frank is a good comedian.
What kind of statement is "Some people aren't nice"?
O
In the following argument: "I think people aren't compassionate enough. If they were, they'd give more to charity." What is the implicit premise?
People don't give more in charity.
Jimmi has a gentle soul; if there is a heaven, he should go to it when he dies.
People with gentle souls go to heaven.
Once I started wearing this copper wristband, that bad cough I had went away. The wristband must have somehow made it stop.
Post Hoc Ergo Proper Hoc
Why do you think that President Obama is a good president? -Well, after be became president, I got a good job and found the wife of my dreams, so he sure helped me a lot.
Post Hoc.
According to Nature, today's thoroughbred racehorses do not run any faster than their grandparents did. But human Olympic runners are at least 20 percent faster than their counterparts of fifty years ago. Most likely, racehorses have reached their physical limits, but humans have not.
Premise: According to Nature, today's thoroughbred racehorses do not run any faster than their grandparents did Premise: Human Olympic runners are at least 20 percent faster than their counterparts of fifty years ago Conclusion: have reached their physical limits, but humans have not
Because all Communists are Marxists, all Marxists are Communists.
Premise: All Communists are Marxists Conclusion: All Marxists are Communists
Because all Communists are Marxists, all Marxists are Communists.
Premise: All Communists are Marxists Conclusion: All Marxists are Communists
Hey, he can't be older than his mother's daughter's brother. His mother's daughter has only one brother.
Premise: His mother's daughter has only one brother Conclusion: He isn't older than his mother's daughter's brother
If the butler had done it, he could not have locked the screen door. Therefore, because the door was locked, we know the butler is in the clear.
Premise: If the butler had done it, he could not have locked the screen door Premise: The screen door was locked Conclusion: The butler is in the clear
If the butler had done it, he could not have locked the screen door. Therefore, because the door was locked, we know the butler is in the clear.
Premise: If the butler had done it, he could not have locked the screen door Premise: The screen door was locked Conclusion: The butler is in the clear
"Let me demonstrate the principle by means of logic," the teacher said, holding up a bucket. "If this bucket has a hole in it, then it will leak. But it doesn't leak. Therefore, obviously, it doesn't have a hole in it."
Premise: If this bucket has a hole in it, then it will leak Premise: It doesn't leak Conclusion: It doesn't have a hole in it
Chances are I'll be carded at JJ's because Kera, Sherry, and Bobby were all carded there, and they all look as though they're about thirty.
Premise: Kera, Sherry, and Bobby were all carded at JJ's Premise: They all look as though they're about thirty Conclusion: I'll be carded at JJ's
I am sure Marietta comes from a wealthy family. She told me her parents benefited from the cut in the capital gains tax.
Premise: Marietta told me her parents benefited from the cut in the capital gains tax Conclusion: Marietta comes from a wealthy family
Presbyterians are not fundamentalists, but all born-again Christians are. So, no born-again Christians are Presbyterians
Premise: Presbyterians are not fundamentalists Premise: All born-again Christians are fundamentalists Conclusion: No born-again Christians are Presbyterians
Seventy percent of freshmen at State College come from wealthy families; therefore, probably about the same percentage of all State College students come from wealthy families.
Premise: Seventy percent of freshmen at State College come from wealthy families Conclusion: About the same percentage of all State College students come from wealthy families
We shouldn't take a chance on this new candidate. She's from Alamo Polytech, and the last person we hired from there was rotten.
Premise: She's from Alamo Polytech Premise: The last person we hired from there was rotten Conclusion: We shouldn't take a chance on the new candidate
That cat is used to dogs. Probably she won't be upset if you bring home a new dog for a pet.
Premise: That cat is used to dogs Conclusion: Probably she won't be upset if you bring home a new dog for a pet
That cat is used to dogs. Probably she won't be upset if you bring home a new dog for a pet.
Premise: That cat is used to dogs Conclusion: Probably she won't be upset if you bring home a new dog for a pet
The Lakers almost didn't beat the Kings. They'll never get past Dallas.
Premise: The Lakers almost didn't beat the Kings Conclusion: They'll never get past Dallas
What is an argument's form?
The structure of an argument that can be expressed with variables and symbols
What are premises?
They are considerations that someone puts forth to convince someone else to accept a conclusion.
This is a good definition of an argument: A conclusion supported by premises.
True
If you read Ayn Rand, you'll be a libertarian. And, of course, if you're an anarchist, you're already a libertarian. Hmm. It looks as if you read Ayn Rand, you'll be an anarchist!
Undistributed middle
if p, then q p Therefore, q This argument is:
VAlid
All M are S No M are P So, some S are not P
Valid
All S are M All M are P So, all S are P
Valid
Evan went to Delaware. People in Delaware don't go on the road trip. So Evan didn't go on the road trip.
Valid
If Jack Davis robbed the Central Pacific Express in 1870, then the authorities imprisoned the right person. But the authorities did not imprison the right person. Therefore, it must have not been Jack Davis who robbed the Central Pacific Express in 1870. is the argument:
Valid
If an argument is sound, it is also:
Valid
If the comet approached within 1 billion miles of the earth, there would have been numerous sightings of it. There weren't numerous sightings. So it did not approach within 1 billion miles. the argument is:
Valid
If they wanted to go to the party, then they would have called by now. But they haven't, so they didn't. is the argument:
Valid
Is the following valid or invalid? That party will be fun. Whenever there's a live band, it's going to be a good party, and they have a live band.
Valid
Is this valid or not? If our daugher is sick, then we have to keep her home. And if we keep her home, we can't go to the conference. So, if our daughter is sick, we can't make it to the conference.
Valid
Is this valid or not? Look, she isn't home. If she was home, then there would be some lights on.
Valid
Ken always gets left out of the fun. That's why he is so shy, since people who get left out become shy.
Valid
Mike can't be a lawyer. He is afraid of public speaking, and anybody who is afraid of public speaking can't be a lawyer.
Valid
Nobody who listens to Classic rock takes Justin Beiber seriously. But some of my students take Justin Beiber seriously. So they don't listen to classic rock.
Valid
She works very hard. And nobody who works hard fails. So, she will not fail.
Valid
Some S are M All M are P So some S are P
Valid
That animal is definitely not a rabbit. Rabbits have tall ears, and that animal doesn't.
Valid
The alternator is not working properly if the ammeter shows a negative reading. The current reading of the ammeter is negative. So, the alternator is not working properly. is the argument:
Valid
The patriots are a successful franchise. Any team with three Superbowl victories is successful, and the Pats have three.
Valid
Valid or invalid? I'm not going to pass the class. If you pass, you have to study hard, and I'm not studying hard.
Valid
Betty got an A in the course, so she must have received an A on the final.
You can't get an A in a course without having gotten an A on the final.
Colonel Mustard could not have murdered Professor Plum because the two men were in separate rooms when the professor was killed.
You can't murder an individual who isn't in the same room as you when he or she is killed.
If she was still interested in me, she would have called, but she didn't.
[Unstated Conclusion]: She is not still interested in me
Indicate which blanks would ordinarily contain premises and which would ordinarily contain conclusions.
________ premise and ________ premise . Therefore, ________. conclusion ________ premise . So, because ________ premise , ________. conclusion ________ conclusion , clearly. After all, ________. premise Because ________ premise and ________ premise , ________. conclusion ________. premise Consequently, ________ conclusion , because ________ premise and ________. premise
The word "so" introduces
a conclusion.
Why do I think that the Republican party has the right answers to America's problems? Because my Math teacher told me, and he is really smart.
appeal to false authority
Greg: I think you should vote against Deval Patrick in the election. Eben: Why do you think that, boss? Greg: Because if you don't, I will fire you. What did Greg do?
appeal to force
Buhler: Blazing Saddles is the best movie of the 20th century? Matthew: Why? Buhler: Because nobody has proven otherwise.
appeal to ignorance
Francis: I think you are having an affair! Mikaela: no I am not! Why would you say that? Francis: until you disprove my claim, I will continue to believe it. What did Francis do?
appeal to ignorance
How do you know that Dell makes the best computers? -Nobody has shown me otherwise.
appeal to ignorance
If the comet approached within 1 billion miles of the earth, there would have been numerous sightings of it. There weren't numerous sightings. So it did not approach within 1 billion miles. the argument is:
valid
Is the following argument valid or invalid? 1. If p, then not-q 2. q, 3. Therefore, not-p
valid
Is the following argument valid or invalid? 1. unless q, r 2. not-r 3. Therefore, q
valid
