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Elements of Arguments        2
Elements of Arguments: Reasons        2
Elements of Arguments: Conclusions        3
Elements of Arguments: Intermediate Conclusions        3
Elements of Arguments: Assumptions        4
Elements of Arguments: Counter-Arguments        4
Elements of Arguments: Indicator Words        5
Evidence Sampling        6
Evidence Sampling: Misrepresenting the Data        6
Evidence Sampling: Insufficient Data        7
Evidence Sampling: Unrepresentative Data        7
Logical Fallacies        9
Logical Fallacies: Ad Hominem        9
Logical Fallacies: Appeal to Authority        9
Logical Fallacies: Appeal to History        9
Logical Fallacies: Appeal to Popularity        10
Logical Fallacies: Circularity        10
Logical Fallacies: Confusing Necessary and Sufficient Conditions        11
Logical Fallacies: Correlation not Causation        11
Logical Fallacies: Inconsistency        11
Logical Fallacies: Generalisation        12
Logical Fallacies: Restricting the Options        12
Logical Fallacies: Slippery Slope        13
Logical Fallacies: Straw Man        13
Logical Fallacies: Tu Quoque        14
Logical Fallacies: Weak Analogy        14

myice

Elements of Arguments
An argument, in Critical Thinking, is not just a conversation in which two people hurl abuse at each other. Neither is it the same thing as straightforward disagreement; there’s a difference between arguing with someone and merely contradicting them.
As Monty Python’s Argument Clinic sketch puts it, an argument is “a collected series of statements to establish a definite proposition”, an attempt to persuade by offering reasons. Any statement that attempts to persuade you that something is true by offering at least one reason for thinking that it is so counts as an argument.
The main Elements of Arguments are thus reasons and a conclusions. The ability to read a passage and pick out its conclusions and the reasons offered in support of it is perhaps the most basic skill required for Critical Thinking.
As you progress to more complicated arguments, you’ll also need to be able to spot intermediate conclusions and counter-arguments. Indicator Words can be helpful in flagging up how different parts of a passage are functioning in the argument that it contains.

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Elements of Arguments: Reasons
The reasons in an argument are the claims made in an attempt to persuade you that the conclusion is true.
The Because Test
A test that can help you to identify the reasons in a passage is the ‘because test’. Simply insert the word “because” into the passage directly before the phrase that you think is a reason. If the passage makes sense, then you’ve probably got the right section. If it doesn’t, then you haven’t.
Quote!
When you’re asked to identify the reasons in a passage, you must give direct quotations. You’re being asked to pick out a specific claims that the passage makes in attempting to prove its conclusion. If you give a rough paraphrase, then you risk changing the claim, resulting in inaccuracy in your answer and so losing you marks.

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Elements of Arguments: Conclusions
The conclusion of an argument is the main point that it is trying to get you to accept. You’ll often (but not always) find this statement either at the beginning or the end of a passage. It may be indicated by a word such as “therefore”, “thus”, or even “in conclusion”.
The Therefore Test
A test that can help you to identify the conclusion of a passage is the ‘therefore test’. Simply insert the word “therefore” into the passage directly before the phrase that you think is the conclusion. If the passage makes sense, then you’ve probably got the right section. If it doesn’t, then you haven’t.
Quote!
When you’re asked to identify the conclusion of a passage, you must give a direct quotation. You’re being asked to pick out a specific phrase that the rest of the passage is trying to get you to accept. If you give a rough paraphrase, then you risk changing the meaning of the phrase slightly, and so giving an inaccurate statement of the conclusion. This can lose you marks. Even missing out a word or two can change the meaning of the conclusion resulting in inaccuracy in your answer. To err on the side of caution, always quote word-for-word.

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Elements of Arguments: Intermediate Conclusions
An intermediate conclusion is something in an argument that functions both as a reason and as a conclusion.
To function as a reason, it must offer support to the main conclusion of the argument (or to another intermediate conclusion).
To function as a conclusion, there must be something else in the argument that lends it support.
Take, for example, the following argument: “Your face is covered in chocolate, so it must have been you that ate my cake, so you owe me a cake.” The main conclusion of this argument is the final clause: “You owe me a cake.” This is supported by the previous clause, which is therefore functioning as a reason, “it must have been you that ate my cake.” This clause, though, is also supported by the previous clause, “Your face is covered in chocolate”, so it is both a conclusion and a reason; it is an intermediate conclusion.

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Elements of Arguments: Assumptions
An assumption, for the purposes of A-level Critical Thinking, is an unstated reason. It is something that must be true for an argument to work, but which is not explicitly stated in the argument.
For example, the argument “The college address is the same street as I’m standing on; therefore, the college must be nearby” assumes that the street isn’t very long. If the street is long, then the college could be on it but still miles away.
The Negative Test
To test whether something is assumed by an argument, you can use the negative test. This involves inserting the opposite of the alleged assumption into the argument and seeing if it still makes sense.
For example, to test whether the above argument assumes that the street isn’t very long, we would check whether this makes sense: “The college address is the same street as I’m standing on; the street is very long; therefore, the college must be nearby.”
With the opposite of the alleged assumption inserted, the argument clearly doesn’t make sense, so the alleged assumption must be true for the argument to work; it is assumed by the original argument.
Don’t Quote!
When answering a question that asks you to identify an assumption, unlike when answering other questions, you should never give a quote from the text; by definition, assumptions are unstated.

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Elements of Arguments: Counter-Arguments
A counter-argument is an argument that goes against the author’s main conclusion. Typically, counter-arguments are considered and rejected in an attempt to strengthen the author’s case.
For example, “If Superman and Spiderman had a fight, then Superman would win as his ability to fly would mean he could attack from any angle. You might think that Spiderman’s ability to hurl webs (a ranged weapon) would give him the edge, but Superman would be manoeuvrable enough to dodge them.”
In this passage, the main conclusion is “If Superman and Spiderman had a fight, then Superman would win”. The reason given in support of this is “his ability to fly would mean he could attack from any angle”.
Also considered, though, is an argument that Spiderman would win: “Spiderman’s ability to hurl webs (a ranged weapon) would give him the edge”; this is a counter-argument.
It is then dismissed with the comment “Superman would be manoeuvrable enough to dodge them”.

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Elements of Arguments: Indicator Words
There are certain words that often indicate the presence of a particular element of an argument. These are called indicator words. Not every element of an argument is flagged up by an indicator word, and not every use of an indicator word is associated with an element of an argument, but indicator words are useful guides.
Conclusions
Conclusions are often indicated by one of the following words or phrases: “therefore”; “thus”; “hence”; “so”; “in conclusion”; “consequently”; “showing that”; “demonstrating that”; “proving that”; “establishing that”; “meaning that”; “entails that”; “implies that”; “as a result”. In past papers, conclusions have often been statements about how we ought to respond to something, so “should”, “must”, and “ought to” should also be treated as indicator words, albeit cautiously.
Reasons
Indicator words for reasons include the following: “because”; “as”; “since”; “in order to”; “otherwise”. Sometimes authors enumerate their reasons, writing “First, ...”, “Second, ...”, “Third, ...” etc., which can also help in their identification.
Counter-Arguments
Counter-arguments can be given away by phrases like “some might argue that”, “it has been suggested that”, or equivalent phrases. The main giveaway for counter-arguments, though, is that the reason(s) cited count against the author’s conclusion rather than for it.

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Evidence Sampling
When presented with observational evidence to support a claim, we need to be wary. It is said that there are lies, damned lies, and statistics, and that you can devise a survey to prove anything that you want. If we are told “A study has shown that...” then we should think twice before we accept the conclusion that is drawn from it.
Misrepresenting the Data
The most basic mistake in interpreting evidence is simply misrepresenting the data. If the observational data do not fit the inference drawn, then there is a problem. There is the possibility of deliberate distortion, accidental misinterpretation, and selectivity.
Insufficient Data
A more common error is drawing a conclusion from insufficient data. Every study has a margin of error, and the smaller the study the greater this will be. Studies with a significant margin of error always leave doubt about any conclusions based on them, so it is important to consider the quantity of data in a study in assessing its validity.
Unrepresentative Data
A constant danger in empirical studies is unrepresentative data. A study that has a sufficient quanity of data may nevertheless be flawed due to insufficient quality of evidence. For a general conclusion to be drawn with any confidence from a limited data set, it must be reasonable to believe that the data set is representative.