Module 1 Exam - Foundations of Logical Reasoning

The lamp is light pink.

No effect. The color of the lamp doesn't make it more or less plausible that the bulb is faulty

Roses are red, and violets are blue. Sugar is sweet, and so are you!

Not an argument. None of these statements provide evidence for the others

Which is the most charitable missing conclusion to add to the following enthymeme? Neville is a talented singer, and talented singers make great karaoke party guests.

Neville will make a great karaoke party guest

Determine whether the following arguments are best classified as being deductive or inductive. Reference: Ref 1-9 Some citizens prefer to live overseas. My uncle lives overseas. Thus, my uncle is a citizen.

inductive

Determine whether the following arguments are best classified as being deductive or inductive. Reference: Ref 1-9 The coin came up heads on the last toss. It probably will come up tails on the next toss.

inductive

I think, therefore I am

argument: I am

when is a deductive argument unsound?

if it is either 1)invalid or 2) one or more of its premises are not true

when is a deductive argument sound?

if it is valid and all of its premises are true.

when is a deductive argument invalid?

if its premises fail to secure the truth of its conclusion.

when is a deductive argument valid?

if its premises secure the truth of its conclusion

Searching for God is a futile endeavor, because He doesn't exist in space and time

Argument. A reason is given for the conclusion that we should not search for God

If all three of us put our minds together, we'd probably come up with a great group project. Butthat would mean we'd all have to make an effort, and although you and I are committed, I'm notsure that Phil is reliable. So I think that we should explain to Phil how important this project is tous, and make sure that we get the best grade on this group project that we can

Argument. Reasons - the same as in i. - are given for a different conclusion

Seb doesn't work at Starbucks, Café Nero, or Dunkin' Donuts. So Seb probably doesn't like coffee

Argument. Reasons are given - not very good ones, but still! - for the conclusion

The exam's range of A scores is 90-100. I got a 98 on the exam. It thus follows necessarily that I got an A on the exam

Deductive Argument. The conclusion is purported to be certain ("necessarily") on the basis ofthe premises

Every insect has six legs. What's crawling up my thigh is an insect. So, what's crawling up mythigh has six legs

Deductive Argument. The first premise asserts something about every insect, and the secondasserts something about a particular insect. The conclusion follows certainly, if both premises aretrue.

The exam's range of A scores is 90-100. I got an A on the exam. So, I got a 98 on the exam

Inductive Argument (though this might be stretching charity a bit). The conclusion isobviously not certain on the basis of the premises, and so it is charitable to interpret this as aninductive argument, though it may also be an especially bad deductive argument.

Most insects have six legs. What's crawling up my thigh is an insect. So, what's crawling up my thigh probably has six legs.

Inductive Argument. The word "most" in the first premise and the word "probably" in theconclusion indicates that the argument is only meant to establish that the conclusion is likely.

Private healthcare insurers can refuse to cover the expenses of people with preexisting medical conditions. In a modern society, every citizen deserves the right to affordable healthcare

No modern society should rely solely on private healthcare insurers

Phil came through on the project. All three of us got a B+ for the group assignment. Maybethis professor saw that we really put in the effort this weekend. Shall we celebrate by taking the night off studying and going to the movies

Not an argument - but a happy outcome!

There is biological evidence that the genetic characteristics for lactose intolerance have beenselected over time by the species. In addition, the height and weight of humans has increased over the centuries

Not an argument. Neither statement is evidence for the other.

Russia and China have recently negotiated an economic alliance that means they no longer need to rely upon the US dollar as an intermediary currency. News agencies in both countries are reporting this, but the US media is largely focused upon the upcoming election. Many US citizens rely only upon national media outlets like CNN and Fox.

Not an argument. None of these statements provide evidence for the others

On the one hand, Rae is a really sweet girl who dresses well. On the other, she can be pretty annoying and I think I like Cici more anyway

Not an argument. Two statements are made

Put in your best effort when effort is required. Effort is required every single day of your life

Put in your best effort every single day of your life.

Shaquelle secretly rolled two six sided dice, and told Mel that neither one had come up with asix. So, it's likely that the total of Shaquelle's dice rolls is less than 8

Strong. If neither dice came up a six, there are six combinations that yield a result equal to orgreater than eight: 5/3, 5/4, 5/5, 4/4, 4/5, 3/5. The remaining nineteen combinations yield a resultless than or equal to seven: 1/1, 1/2, 1/3, 1/4, 1/5, 2/1, 2/2, 2/3, 2/4, 2/5, 3/1, 3/2, 3/3, 3/4, 4/1,4/2, 4/3, 5/1, 5/2. The probability of getting less than eight is thus 19/25, which is likely.

The exam's range of A scores is 90-100. B scores are 80-89, C scores are 70-79, D scores are60-69, and F scores are 0-59. I know that I didn't get a 99 or 100 on the exam. So, I probably didn't get an A on the exam.

Strong. If you didn't score 99 or 100 on the exam, there are 99 remaining scores you couldhave received. If you scored any of the 90 scores between 0-89, you did not get an A. If youscored any of the 9 scores between 90 and 98, you did get an A. The probability of not getting anA given theses premises is thus 90/99, which is likely.

No shiny objects are blue objects. No shiny objects are large objects. So, no blue objects are large objects

The logical form of the argument is: No S are B No S are L No B are L LA counterexample (an argument sharing this form with true premises and a false conclusion) is: No sons are daughters No sons are mothers No daughters are mothers

All planetary bodies are stargazing targets. All planetary bodies are luminescent bodies.Hence, all luminescent bodies are stargazing targets.

The logical form of this argument is: All P are S All P are L All L are SA counterexample is: All mothers are female All mothers are people older than 5 All people older than 5 are fem

No physics majors are shoplifters. No physics majors are lifeguards. So, no lifeguards are shoplifters.

The logical form of this argument is: No P are S No P are L No L are SA counterexample is: No cats are cops No cats are humans No cops are humans

If there really were an all-loving God looking down on us, then there wouldn't be so muchdeath and destruction visited upon innocent people.

There isn't an all-loving God looking down on us

The ceiling light does not work

Weakens the argument. If the ceiling light does not work either, then perhaps there is a power cut

Which is the most charitable missing conclusion to add to the following enthymeme? Voting for a political candidate who shares your political outlook is crucial. It's a bad idea to be a one-issue voter, for that reason. I know you think that abortion is morally wrong, and the Republican candidate claims to agree. But the Democratic candidate defends policies much closer to your views, like universal healthcare.

You should vote for the Democratic candidate.

argument

a set of propositions, one of which (the conclusion) is (supposed to be) supported by the others (the premises)

Determine whether or not the following passages contain arguments. Reference: Ref 1-7 My brother is going to make a lot of money. Phone apps are big business. Some apps are expensive. Of course, others cost a lot. My brother is creating some new games that he will market as apps.

argument

It is true that 1+4 =5, and it is also true that 2 + 3 = 5. Thus, we can conclude with certainty that (1 + 4) = (2 + 3).

argument: (1 + 4) = (2 + 3)

I believe that humans will evolve into androids, because we will eventually be able to replaceall organic body parts with artificial parts. In addition, we will be able to live virtually forever bysimply replacing the parts when they wear out or become defective.

argument: I believe that humans will evolve into androids

We should never take our friends for granted. True friends are there when we need them. They suffer with us when we fail, and they are happy when we succeed

argument: We should never take our friends for granted

You should wear a facemask when you go outside. We are experiencing a global pandemic.Scientists have demonstrated that wearing a facemask impedes the spread of disease

argument: You should wear a facemask when you go outside.

Since television commercials disrupt the flow of programs, and given that any disruptionimpedes the continuity of a show, consequently we can safely say that commercials are a bad thing

argument: commercials are a bad thing

They say that "absence makes the heart grow fonder," so my teachers should really love me since I have been absent for the last 2 weeks

argument: so my teachers should really love me

The president doesn't understand the threat we face. He won't even use the phrase "Radical Islamic Terror."

create a charitable reconstruction: Anyone who doesn't use the phrase "Radical Islamic Terror" doesn't understand the threat we face.

Cockfighting is an exciting pastime enjoyed by many people. It should therefore be legal

create a charitable reconstruction: Exciting pastimes that are enjoyed by many people should be legal

I'm having a conversation with a mammal. Thus, I'm having a conversation with a human.

create a charitable reconstruction: Humans are the only mammals that I can have a conversation with

Determine whether the following arguments are best classified as being deductive or inductive. Reference: Ref 1-9 All motorcycles are fast machines. Lou owns a motorcycle. So, Lou's motorcycle is a fast machine.

deductive

Consider the following passage: "Mrs. Wendicott went shopping this morning. She bought three frozen dinners. She also bought a large cake. I saw her walking home." This passage

does not contain an argument

For each of the following passages, decide whether it is an argument or an explanation. Reference: Ref 1-8 There has been an overall decrease in violence among humans worldwide throughout recorded history. Biologically speaking, this is because the genetic characteristics for nonviolence have been selected over time by the species.

explanation

An argument is any group of statements.

false

An argument must have at least two premises.

false

Determine whether the following arguments are best classified as being deductive or inductive. Reference: Ref 1-9 Most apples are red. I am eating an apple. So I am eating something red.

inductive

Consider the following argument: Argument 4 Paris's Eiffel Tower is three times as tall as the one in Las Vegas. The Luxor Pyramid in Las Vegas is half the size of the original in Egypt. The Statue of Liberty in New York is four times the one in Las Vegas. Thus, every object in Las Vegas is smaller than in other cities. Is the statement "Paris's Eiffel Tower is three times as tall as the one in Las Vegas." a premise or a conclusion of the argument?

premise

Consider the following argument: Argument 5 You know, I believe that we should stop interfering in other countries' affairs. This follows from the fact that we have no moral right to change a country's way of governing itself. Also, interfering often gets us locked into combat; not to mention that the potential for loss of lives on both sides is high. In addition, the cost of waging wars is astronomical. Any engagement means weakening our already shaky economy. Add the fact that interfering makes us have more enemies around the world who feel threatened by us. Is the statement "Any engagement means weakening our already shaky economy" a premise or a conclusion of the argument?

premise

Consider the following argument: Argument 5 You know, I believe that we should stop interfering in other countries' affairs. This follows from the fact that we have no moral right to change a country's way of governing itself. Also, interfering often gets us locked into combat; not to mention that the potential for loss of lives on both sides is high. In addition, the cost of waging wars is astronomical. Any engagement means weakening our already shaky economy. Add the fact that interfering makes us have more enemies around the world who feel threatened by us. Is the statement "The cost of waging wars is astronomical" a premise or a conclusion of the argument?

premise

What is the premise and argument in this example? All men are mortal. Socrates is a man. Therefore, Socrates is mortal.

premises: all men are mortal. socrates is a man. therefore, argument: socrates is mortal

common premise indicators

since because for for the reason that given that seeing as inasmuch as after all it follows from assuming that

proposition

something that is stated of claimed to be true

Consider the following argument: The detective knows that the murderer is either the maid, the cook, or the butler. The murderer left floury fingerprints at the scene of the crime The cook is the murderer Would adding the following statement as a new premise strengthen, weaken, or neither strengthen nor weaken the argument? The maid has an alibi for the crime

strengthen

The lamp is plugged into the wall socket correctly

strengthens the argument. If the lamp is plugged into the wall socket correctly, the flaw does not lie in the electrical connection

Your radio is working, and it is connected to the same outlet as the lamp.

strengthens the argument. If the radio plugged into the same socket is working, then electricity is flowing to the socket

common conclusion indicators

that therefore thus so consequently wherefore hence for this reason it follows that we may infer that which implies that

An invalid argument is automatically an unsound argument.

true

Some strong arguments are weaker than other strong arguments

true

Consider the following argument: Argument3 Paris is called the "City of Lights." Las Vegas is also called the "City of Lights." So, there must be at least two cities with the same nickname. Is the statement "Las Vegas is also called the "City of Lights."" a premise or conclusion of this argument?

premise

You hate getting those prank phone calls, so why don't you switch your number?

component statements in the sentences as necessary: You hate getting prank phone calls You should switch your number

If all three of us put our minds together, we'd probably come up with a great group project. Butthat would mean we'd all have to make an effort, and although you and I are committed, I'm notsure that Phil is reliable. So I think that we should expect a bad grade on this project, and insteadwork on other assignments this weekend.

Argument. Reasons are given for a conclusion

deductive argument

claims to make the conclusion certain on the basis of the premises

inductive argument

claims to make the conclusion probable on basis of the premises

At fifteen, you are simply too young to go to college. Even if you're a genius who aces theSATs early, you'll lack the social maturity needed to succeed. College is about more than academics

Argument. Reasons are given for thinking that fifteen is too young to go to college

Our toaster ovens have the best energy efficiency rating on the market. We have a lot of loyal,repeat customers, who know that our brand is reliable. Moreover, there's an excellent specialoffer this month that would mean you'd get an electric kettle, too. So, you should really buy oneof our toaster ovens!

Argument. Reasons are given for why it is true that you should buy a toaster oven.

Pedro flipped a coin ten times, and every single time it came up heads. That's prettyastonishing! I predict that next time it will come up heads, too

Weak. If Pedro's coin is fair, the chance of the next toss coming up heads is exactly 50%

The exam's range of A scores is 90-100. I got an A on the exam, so I must have scored 100

Weak. The probability of getting a 100 given that you scored in the 90-100 range is only 1/11or 9%

Since television commercials help pay the cost of programming, and because I can always turn off the sound of the commercials, go to the bathroom, or get something to eat or drink, it follows that commercials are not such a bad thing.

argument: commercials are not such a bad thing.

At one time Gary Kasparov had the highest ranking of any chess grand master in history.However, he was beaten in a chess tournament by a computer program called Deep Blue, so the computer program should be given a ranking higher than Kasparov

argument: the computer program should be given a ranking higher than Kasparov

If you start a strenuous exercise regimen before you know if your body is ready, you can cause serious damage. Therefore, you should always have a physical checkup before you start a rigid exercise program.

argument: you should always have a physical checkup before you start a rigid exercise program

In America, the freedom of individual citizens is the most fundamental value. Some citizensdo not want to wear facemasks. They are uncomfortable. Disposable masks are also bad for theenvironment. So you shouldn't wear a facemask when you go outside

argument: you shouldn't wear a facemask when you go outside

Greta the genie just offered me eternal wealth, health, beauty, or happiness. The decision iseasy! Beauty fades. Money can't buy you love. Everyone's happy sometimes. But you can't doanything once you're sick or dead. Health for me, please, Greta!

component statements in the sentences as necessary: Greta the genie offers me the choice between eternal wealth, health, beauty, or happiness. Beauty fades. Money can't buy me love. Everyone is happy sometimes. You can't do anything once you're sick or dead. I choose eternal health

Both the Titanic and the Challenger tragedies could have been avoided, you know.Engineering experts were ignored by financiers and politicians. In both cases, materials faileddue to thermal effects. The steel hull of Titanic was below its ductile-to-brittle transitiontemperature. And the rubber of Challenger's O-rings lost pliability in sub-freezing temperatures.

component statements in the sentences as necessary: In the Titantic and Challenger tragedies, engineering experts were ignored by financiers and politicians. In the Titantic and Challenger tragedies, materials failed due to thermal effects. The steel hull of Titanic was below its ductile-to-brittle transition temperature. The rubber of Challenger's O-rings lost pliability in sub-freezing temperatures. Both the Titanic and the Challenger tragedies could have been avoided

Do you like delicious food? How about fun games? And I know you like cool prizes. Wellthen, Chuck E. Cheese's is the place for you

component statements in the sentences as necessary: You like delicious food You like fun games You like cool prizes Chuck E. Cheese's is the place for you

Consider the following argument: Argument 2 Want to know why soy bean curd has no taste? Well, the fat in hamburgers is what gives them their great taste. And the fat in pizza is what gives it great taste. In general, food without fat tastes bland. And soy bean curd has no fat. Is the statement "Soy bean curd has no taste" a premise or conclusion of this argument?

conclusion

Consider the following argument: The detective knows that the murderer is either the maid, the cook, or the butler. The murderer left floury fingerprints at the scene of the crime The cook is the murderer Would adding the following statement as a new premise strengthen, weaken, or neither strengthen nor weaken the argument? The detective was good friends with the victim

neither strengthen nor weaken