Critical thinking revision: A guide to flaws – AS level revision notes!

AS level critical thinkers listen up, here’s your one stop shop for revision notes and guides to flaws for your exams this year.

Ditch the expensive revision books for this course as we’ve got it all covered from generalisations to the countless types of irrelevant appeals. Unfortunately it is very much a wall of text so we’ve added some inspiring thinking GIFs to get you in the right mind set.


Straw man

A straw man argument or flaw occurs when an arguer ‘misses the point’ of, distorts or exaggerates an opposing argument. This may be done on purpose to make it easier to write a counter argument or it may be because the original argument was poorly written. For example:

Person A: I am for the war in Iraq as it has given Iraqis more freedom
Person B: Person A is in favour of our troops killing innocent Iraqi children and abusing children, this is wrong, therefore the war on Iraq is wrong.

Here Person B is guilty of a straw man argument by misrepresenting what was actually said by Person A in order to make it easier to create a counter argument.

Flaw of causation

The flaw of causation, also known as a ‘correlation not causation’ flaw is committed by reasoning that because two events happen together there is a direct link between the two. In simple terms:

A happened before B, therefore A caused B

The flaw here is not considering any other reasons or explanations for the two events happening together, it could something else, C, causes both A and B or that they happened completely independently by coincidence.

The simple fact that there is a correlation between two things does not imply causation.

thinking 4


Conflation happens when an argument brings two or more concepts, actions or ideas together and treats them as the same thing. Typically the concepts involved share many similarities but it still doesn’t mean they can be interchanged with one another. For example:

Too many people in our country are fat. Unfit people put a strain on the health service, we should therefore encourage the government to help people loose weight.

Here the terms ‘fat’ and ‘unfit’ are conflated. Whilst it is true that many fat people are unfit it is not the case for everyone who is overweight and vice versa.

The problem with conflation is that it the argument starts to fall apart. If it is unfit people putting a strain on the health service then the government doesn’t just need to help people loose weight but lead healthier life styles in general: There will be unfit people are who are not necessarily overweight, for example smokers and heavy drinkers.

Restricting The Options

This type of flaw is often also called a ‘false dilemma’. It is an attempt to justify an action or conclusion by making it seem as though there aren’t any other options. For example:

The big bang theory must be true, the only other option is some sort of super being ‘creator’ which is unlikely.

This argument ignores any other theories for the creation of the universe.


A generalisation uses a specific case or specific evidence to support a general conclusion. For example:

I saw video footage of a police officer hitting a member of the public therefore all police are thugs

Here the flaw is quite obvious; we simply cannot use such a specific case about a single police officer to draw a conclusion about all police officers.

A generalisation may also be ‘sweeping’, which involves drawing a conclusion of all from many. For example:

Most men like football, therefore all men like football.

Again the flaw here is obvious, we cannot move from many to all.

Generalisations are often the result of stereotypes and prejudice.