Chapter 1

Question 1

Deductive reasoning

Answer 1

Spelling out whatever conclusion follows logically from your premises, without reference to any external information

Question 2

Deductive proof

Answer 2

Demonstrating that a particular conclusion logically follows from certain premises, and that this conclusion must be true if these premises are true

Question 3

Truth-preserving

Answer 3

when used correctly, deductive reasoning is guaranteed to preserve the truth of its premises is its conclusion.

Question 4

Unwarranted

Answer 4

A conclusion that is not supported by the argument

Question 5

Necessary condition

Answer 5

Must be met if something is to be true, but cannot by itself guarantee the truth of that thing

Question 6

Sufficient condition

Answer 6

One that, if met, does guarantee the truth of something

Question 7

Logic

Answer 7

The study of the principles distinguishing correct from incorrect reasoning

Question 8

Affirming the antecedent

Answer 8

A valid form of argument in which, because one thing is said always to follow from another, the truth of the first guarantees the second is also true

Premise 1: Premise 2: Conclusion:
If A, then B. A. Therefore, B.

Question 9

Formal fallacy

Answer 9

An invalid form of argument representing an error in logic, meaning that arguments in this form cannot be relied on to arrive at valid conclusions

Question 10

Affirming the consequent

Answer 10

An invalid argument which mistakenly assumes that, when one thing always follows from another, the truth of the second also guarantees the first

Premise 1: Premise 2: Conclusion:
If A, then B. B. Therefore, A.

Question 11

Denying the consequent

Answer 11

A valid form of argument in which, because one thing is said always to follow from another, the fact that the second isn’t true also guarantees the first isn’t true

Premise 1: Premise 2: Conclusion:
If A, then B. Not B. Therefore, not A.

Question 12

Denying the antecedent

Answer 12

An invalid argument which mistakenly assumes that, when one thing always follows from another, the fact that the first isn’t true also guarantees the second isn’t true

Premise 1: Premise 2: Conclusion:
If A, then B. Not A. Therefore, not B.

Question 13

Sound Argument

Answer 13

A deductive argument that is both valid and has true premises, meaning its conclusion must also be true

Question 14

Unsound Argument

Answer 14

An argument that does not meet the standard of soundness, either because it is invalid or because one or more of its premises is untrue, or both

Question 15

Inductive reasoning

Answer 15

A form of reasoning in which premises strongly support

a conclusion, but where we can never be absolutely certain that it is true

Question 16

Ampliative reasoning

Answer 16

Another way of describing inductive reasoning – intended to show that such reasoning works by ‘amplifying’ premises into a broader conclusion

Question 17

Ranking inductive arguments

Answer 17

Determining which arguments are more or less convincing relative to one another

Question 18

Inductive strength or inductive force

Answer 18

A measure of how likely we believe an inductive argument is to be true

Question 19

Cogent

Answer 19

An inductive argument that has a good structure, but whose conclusion we should not necessarily accept as true (similarly to a valid deductive argument)

Question 20

Inductively forceful

Answer 20

An inductive argument that has both a good structure and true premises, and whose conclusion we thus have good reason to accept as true (similarly to a sound deductive argument, although without its certainty)

Question 21

Implicit qualification

Answer 21

When a general statement is not literally intended, some implicit qualification needs to be assumed, indicating the frequency with which it applies

Question 22

Rational expectation

Answer 22

Whatever it would be most reasonable to expect in a particular situation; this can be quite different to what somebody personally expects

Question 23

Sample

Answer 23

The particular cases you are using to stand for the entire category about which you wish to make an inductive generalization

Question 24

N = 1

Answer 24

A sample size of one indicates an anecdote rather than a serious investigation; any inductive argument based on a single instance is likely to be very weak

Question 25

Representative samples

Answer 25

Closely resemble the larger group about which claims are being made, while unrepresentative samples fail to do so

Question 26

Randomized sample

Answer 26

One selected at random from across a field of study, with no particular element misleadingly over- represented

Question 27

Sampling bias

Answer 27

Biases introduced by imperfect methods of selecting a sample

Question 28

Observational error

Answer 28

Errors due to the accuracy of your measuring system, usually reported as ±X, where X is the potential difference between measured and actual values

Question 29

Margin of error

Answer 29

An expression of the degree to which results based on a sample are likely to differ from those of the overall population

Question 30

The problem of induction

Answer 30

No matter how likely we believe something to be, an inductive argument can never actually prove it to
be true

Question 31

Falsification

Answer 31

The contradiction of something previously accepted as true or obvious

Question 32

Counter-example

Answer 32

An example whose discovery makes
it necessary to rethink a particular position, because it directly contradicts a generalization previously believed to be true

Question 33

Black swan event

Answer 33

An event that defies both previous experience and expectations based on that experience, making it almost impossible to predict

Question 34

Fallacy

Answer 34

A flawed general type of argument that establishes a faulty connection between premises and conclusion, thus failing to give us a good reason to accept the conclusion

Question 35

Fallacious argument

Answer 35

An argument whose conclusion does

not follow from its premises, because its reasoning rests on an identifiable fallacy

Question 36

Appeal to popularity

Answer 36

a fallacious form of argument based on the assumption that whatever most people think must be true.

Question 37

Appeal to irrelevant authority

Answer 37

A fallacious form of argument based on the perceived opinion of an authority without any expertise in a relevant area

Question 38

Unwarranted hidden assumption

Answer 38

The faulty, unstated element of reasoning that a fallacy relies on, and that we aim to spell out in order to identify what is at fault

Question 39

Comparable example

Answer 39

A method for testing potentially fallacious arguments, and illustrating their flaws, by applying exactly the same reasoning in a different context

Question 40

Informal fallacy

Answer 40

If you need to consider both the content of an argument and its relationship with external infor- mation, this is an

Question 41

Formal fallacy

Answer 41

If the error is purely related to the structure of an argument, you are dealing with

Question 42

Fallacy of relevance

Answer 42

An argument relying on premises that are insufficiently relevant to its conclusion for us to accept this conclusion

Question 43

Argument by appeal

Answer 43

The fallacy of appealing to external factors such as authority or popularity to justify a conclusion, rather than using rigorous reasoning

Question 44

Ad hominem

Answer 44

The fallacy of attacking the person making

an argument rather than what they actually say

Question 45

Fallacy of ambiguity

Answer 45

Shifting the meaning of terms during reasoning, or exploiting uncertainty in order to support an unjustified conclusion

Question 46

Equivocation

Answer 46

Using a word in two quite different senses while pretending that they are the same in order to create the appearance of reasoning

Question 47

Amphiboly

Answer 47

Using a phrase or sentence that can be interpreted as meaning more than one thing, without clarifying which

Question 48

The fallacy of composition

Answer 48

Mistakenly arguing that whatever is true of the individual parts must also be true of the whole

Question 49

The fallacy of division

Answer 49

Mistakenly arguing that whatever is true of the whole must also be true of its individual parts

Question 50

Material fallacies

Answer 50

Fallacies that either covertly assume the truth of a conclusion or avoid the real issues at stake

Question 51

Begging the question

Answer 51

putting the conclusion to be proven into your premises,

thus producing something convincing-sounding that proves nothing

Question 52

Circular reasoning

Answer 52

an argument whose premise supports its conclusion, and whose conclusion supports its premise, making it a closed loop

Question 53

Post hoc ergo propter hoc

Answer 53

the fallacy of assuming that, when one thing happens after another, the first thing must be the cause of the second thing

Question 54

Correlation is not causation

Answer 54

the fallacy of assuming that, if two phenomena or sets of data closely follow one another, one must be caused by the other

Question 55

Inverting cause and effect

Answer 55

The fallacy of confusing the direction of causation between two related phenomena, and thus mistakenly labelling an effect as a cause

Question 56

False dilemma

Answer 56

Fallaciously claiming that, in a complex situation, it is only possible for one of two things to be true

Question 57

Loaded/complex question

Answer 57

Asking a question about one thing that also includes an unstated assumption about another, in an attempt to force someone to accept this assumption

Question 58

Faulty analogy

Answer 58

Claiming two things are similar, even though they are not, in order to make an unreasonable conclusion look reasonable

Question 59

Faulty generalization

Answer 59

Using a small amount of evidence to justify a much larger observation that isn’t actually warranted

Question 60

Slippery slope

Answer 60

Arguing on the basis that, if one small thing is allowed to happen, an inevitable and increasingly serious chain of further events will be set in motion

Question 61

The undistributed middle

Answer 61

A formal fallacy which mistakenly confuses something that applies to all members of a category with something that applies only to members of that category

Question 62

Base rate neglect

Answer 62

Ignoring the underlying frequency of one element in
an analysis, and
thus potentially reaching an incorrect conclusion about the likelihood of a certain result

Question 63

False negative

Answer 63

A negative test result produced in error, when whatever is being tested for is in fact present (e.g. a pregnancy test saying you are not pregnant when you actually are)

Question 64

False positive

Answer 64

A positive test result produced in error,
when whatever is being tested for is in fact absent
(e.g. a pregnancy test saying you are pregnant when you actually are not)

Question 65

True positive

Answer 65

a positive test result that correctly corresponds to the presence of whatever you’re testing for

Question 66

Bayes’s theorem

Answer 66

a method for calculating the probability of an event based on our knowledge of previous events

Question 67

Base rate

Answer 67

the initial, underlying likelihood that something we are investigating is the case (e.g. the base rate of disease X in this population is one case per 2,000 people per year)