Critical Thinking Unit 1

What is an argument

An argument has 3 parts- a conclusion, reason/s and persuasive language.
A reason is a cause that makes something happen.
A conclusion is a result or judgement caused by the reason.
Persuasion tries to make you do or believe in something
For an argument to be successful, all of these elements are needed
Counter arguments contradict your views and are included in an argument to highlight how strong your views are
An assertion is similar to an argument, but there are no reasons. An assertion is very persuasive, but it is not substantiated

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The following words/phrases often start conclusions or are part of them- therefore, so, consequently, as a result, hence, thus, it follows that. I hate pasta therefore I will never visit Italy
Must, should, need to and ought to are persuasion words that are often included in a conclusion. You must stop smoking because it is bad for your lungs

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To identify reasons in an argument, put an indicator word (because, as, seeing as, since) in front of the phrase.
The conclusion can be recognised by putting “therefore” in front of it; for example, “Putting “therefore” in front of the conclusion always helps you to identify it. Therefore, you should try to do it whenever you are stuck.”
Evidence and examples can be determined with indicator words such as “for example”, “such as” and “for instance”.
Counter assertions and arguments go against the main view of the argument, they can be identified with indicator words (conversely, on the other hand)
Hypothetical reasoning occurs when a statement is made which uses words such as “if” and “then”. Hypothetical reasoning is used to predict what will happen as a consequence of something else happening.

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To show the structure, make codes for elements of an argument (R=Reason, C= Conclusion)
Evidence and examples support and strengthen reasons- if they are good evidence or examples
Reasons support conclusions. A conclusion can be drawn from good conclusions.
Counter arguments/assertions are included to make the main argument seem stronger and more valid

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An assumption is an unstated part of an argument, without which a conclusion cannot be drawn from the reasons.
You can find the assumption by finding the reason and the conclusion, and the jump between them is the assumption. For example, “The value of shares in the stock market has fallen in recent years. This means that everybody must have suffered some financial losses”, the assumption is that everyone had invested in shares.
Moral or ethical arguments are based on the assumptions that things are good/bad/wrong/right.
In an exam, you are expected to identify the assumption and give an example where this assumption is irrelevant
For example, “Because of global warming, we must reduce our emissions of carbon dioxide”. The assumption is that global warming is a bad thing, whereas, in cold parts of the world the higher temperatures will increase crop yield.

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The function of evidence and examples is to provide support for reasons so the way to judge their strength or weakness is to find the reason and then decide how much support the evidence or example does indeed give
Strengths: An example is strong if it is provided by a person or organisation which has expertise in the field.
Weaknesses: Irrelevance – think carefully about whether the example is appropriate for the reason it is intended to support.
Generalisation – This is the commonest weakness in examples. The example is only one instance but if it is meant to support a reason which applies to many cases, it can be argued that the example might be a special case and cannot be used to generalise.
Is the evidence-
(a) relevant to the reason?
(b) representative of the population?
(c) meaningful (vague, use averages)?
(d) significant?

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The steps involved in identifying the strength of reasoning in arguments are:
1. Identify the conclusion
2. Identify the reason(s)
3. Compare the words in the two parts to see whether the conclusion can be drawn totally from the reasoning. If it can, the reasons give strong support; if it cannot, there is weak support for the conclusion.
4. In the case of the reason giving weak support, you should try to identify the assumption which is needed to fill the gap in the reasoning.
In 2005 Africa was the continent worst affected by HIV (R1). The highest rates were in Southern Africa (R2). The world community should help the countries hit hardest by HIV and in particular the countries in Southern Africa (C).- This reasoning is strong as the reasons act together to support the conclusion
One species in the world, Homo sapiens, is now using a quarter of the resources that nature produces each year (R). This is the main reason why the production of biofuels should not be expanded (C).- This reasoning is weak as it does not support the conclusion, without making assumptions

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When you assess the plausibility of a claim, you assess how reasonable it is. This does not mean that you judge whether it is true; instead, you judge whether it could be true.
A claim is any statement which can be challenged- and includes opinions and general principles
Showing how reasonable the claim is:
1. The assessment- is the claim reasonable
2. Clarify the claim if necessary
3. Consider whether supporting evidence is needed to make the claim plausible
4. Consider whether the claim is based on a reasonable assumption

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