Critical Thinking

Argument Structures

When you are creating a debate or writing an essay, you often need to follow a pattern, or structure, to make sure your argument makes sense. In Critical Thinking, there are two types of argument structure: simple and complex. Using diagrams to help break down an argument is a really good way of seeing how the argument has been pieced together and whether, therefore, it is well reasoned.

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Simple Structure Arguments

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A simple argument follows the pattern of the premises leading directly to the conclusion. This can be nicely expressed in diagram form as below:

Here we can see two types of simple argument - one in which the two premises depend on each other, and one in which the two premises are unrelated statements, but they both reach the same conclusion.

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A T-shaped argument can be:

[P1] Socrates is a man

[P2] All men are mortal

[c] Therefore Socrates is mortal

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whereas a V-shaped argument can be:

[P1] Socrates gets no exercise

[P2] Socrates drinks excessively

[c] Therefore Socrates is unhealthy

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So you can see, in the first instance - the T-shaped argument - the conclusion would not have made sense without both premises, but in the Y-shaped argument, either of the premises could have, by themselves, led to the conclusion.

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Complex Structure Arguments

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But, as I'm sure you are already thinking, this is not how most arguments work in real life - or even in your essays and debates! These tend to follow more complex structures. This is where diagrams can really show you how an argument's structure fits together (or doesn't!). Admittedly, though, they are more difficult to draw...!

Complex arguments involve ‘sub-arguments’ and ‘intermediate conclusions’ which then go on to act as support for the main argument, the conclusion of which is the ultimate point an argument is trying to get us to accept. Let's look at an example which is illustrated in the first diagram above (far left, 'chain of reasoning'):

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TEXT:

‘Most prospective parents would prefer to have sons. Therefore, if the choice is made available, due to advances in technology, it is likely that eventually there will be many more males than females in the population. This would result in serious social problems, so we should prohibit the development of techniques which enable people to choose the sex of their children.’

(AQA Specification)

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Here, the initial premise:

R1) 'Most prospective parents would prefer to have sons.'

only indirectly support the final conclusion. They directly support an intermediate conclusion:

IC) 'If the choice is made available ... it is likely that there will be many more males than females in the population.'

which then goes on to act as support, alongside a further premise:

R2) 'This would result in serious social problems...'

for the main conclusion:

MC) 'So we should prohibit the development of techniques which enable people to choose the sex of their children.'

which is the main point the argument is trying to get us to accept. So you can see, this argument is complex!

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When analysing arguments like this, it can sometimes be better to work backwards - find the conclusion, then see if you can spot the premises which have been used to support it and work out how they all fit together. The reason this is useful is because it helps you to properly confirm that the argument being made is reasoned and not, as we shall see later, a fallacy or assumption...