LNAT (Law National Aptitude Test)

What an argument is

An argument is a set of statements in which some, the premises, are offered as reasons to accept another, the conclusion. A passage is not an argument just because it is about a disputed subject. "The council closed the library in March" is a report. "The council was wrong to close the library, because it was the only free study space in the town" is an argument, since the second half is given as a reason for the first.

Three things are easily mistaken for arguments and are worth telling apart early, because a question that asks for the conclusion has no answer in a passage that only describes or explains.

• A description says what happened or what something is like, and offers no claim that needs support.
• An explanation says why something is the case when everyone already accepts that it is. "The bridge closed because the cables had corroded" explains a closure nobody disputes. An argument tries to persuade someone that a claim is true.
• An opinion on its own has no reasons attached. "Zoos are cruel" becomes an argument only when something is offered in its favour.

The same sentence can be either, depending on whether the point is to convince. "The shop lost customers because prices rose" is an explanation in a business report and the conclusion of an argument in a debate about whether prices caused the decline.

Indicator words

Some words mark a conclusion and some mark a premise. They help, but they are not a substitute for asking what supports what, since plenty of arguments have none and some of the words have other uses ("since" can mean "from then on").

Words such as "clearly", "obviously" and "surely" signal that the author thinks a claim needs no support. They often sit in front of exactly the claim that does.

Finding the main conclusion

The main conclusion is the claim the whole passage is trying to establish. Ask of each candidate: is the rest of the passage there to support this? If the answer is yes, and the claim is not itself used to support something further, it is the main conclusion.

It may come first, last, or in the middle, and a passage can state it in the opening sentence and then spend its length defending it. A useful check is to try to put "because" after a statement and see whether the rest of the passage completes it sensibly. "Museums should be free, because..." works if the remaining sentences are the reasons. "Museums charge for entry, because..." does not, unless the passage goes on to argue that point.

Intermediate conclusions

Arguments often have layers. A claim can be a conclusion in relation to the premises beneath it and a premise in relation to the claim above it.

Public libraries cut loneliness among older people. Loneliness raises the risk of illness, so libraries reduce health costs. Anything that reduces health costs deserves public money, so libraries should keep their funding.

Here "libraries reduce health costs" is an intermediate conclusion, drawn from the first two sentences and then used as a premise for the final claim. The main conclusion is the last sentence. A question that asks what the passage "concludes" wants the main one; a question about the role a sentence plays wants you to notice that it is intermediate.

Stated and unstated parts

Arguments leave things out. A missing premise is treated in the note on assumptions. A conclusion can also be left implicit, as when an author lists the harms of a policy and never writes "so it should be abandoned". In that case the conclusion is what the premises are plainly meant to lead to, and no more than that: adding a stronger claim than the author would accept is a common way to choose a wrong answer.

Different kinds of conclusion

The kind of conclusion shapes what would count as good support for it.

• A factual claim, such as "the new tax reduced sales", is supported by evidence about what happened.
• A causal claim says one thing produced another and needs more than two events occurring together.
• A prediction says what will happen and is only as good as the reasons for thinking present patterns will continue.
• An evaluative claim says something is good, bad, fair or unjust and depends on a standard the author may not state.
• A prescriptive claim says what ought to be done. It needs at least one premise about values or aims as well as one about facts. "The scheme saves money, so it should go ahead" quietly assumes that saving money matters more than whatever the scheme costs people in other ways.

That last point is one of the most useful habits in reading an argument: facts alone never yield an "ought", so look for the value premise that joins them and ask whether the author has defended it.

Working through a short passage

Many people argue that paying jurors would make juries more representative. But payment would also attract people who are attracted by money alone, and they are the least likely to take the job seriously. So paying jurors is not worth the cost.

The first sentence reports a view the author then opposes, so "paying jurors would make juries more representative" is a position under attack rather than the author's own. The second sentence gives a reason against payment. The final sentence is introduced by "so" and is the main conclusion. Mistaking the first sentence for the conclusion is the typical error, caused by reading a view the author reports as a view the author holds.

Notice also the premise that does the work in the middle: that the people attracted by pay would be the least serious. The passage states it without support, which is what a later question on weaknesses will probably ask about.