Premises, conclusions, and statements

An argument is a set of statements, some of which are intended to provide reasons to believe one of the others.

The conclusion of an argument is the statement that is being argued for, the thing that the arguer is trying to convince her audience of.

The premises are the reasons given for believing the conclusion, the evidence that the conclusion is true.

Statements are simply things about which it makes sense to ask “Is it true or false?”  “The sky is blue” is a statement. So is “All cats have tails.”  Not everything we say is like this.  If I say “Please pass the salt”, that is a request – it doesn’t make any sense to ask whether “Please pass the salt” is true or false.  If I say “Shut the door!”, I’m giving an order, not making a statement.  Again, it makes no sense to ask whether “Shut the door!” is true or not.  Questions are not statements either.

​When someone makes a statement, they are claiming that something is true.

Sometimes it is appropriate to ask for evidence for a statement, or reasons why you should believe it. If I assert that marijuana should be legalised, you are unlikely to simply believe me, unless you think anything any university lecturer says is automatically true.  You’ll probably want me to give you some reasons in support of my claim.

When someone provides verbal (written or spoken) evidence for a statement, or reasons to believe a statement, they are giving an argument for that statement.  We call the statements which contain the evidence the premises of the argument. The statement which the evidence is evidence for – the statement that is being argued for –  is called the conclusion.

​How can you tell what the conclusion is?  Sometimes there are indicator-words, for example, “so” in the first argument above is a conclusion-indicator: “because” in the second argument above is a premise-indicator.  (Note however that not every “because” marks a premise in an argument.)

Some conclusion indicators

• therefore
• so
• we can conclude that
• thus
• hence
• consequently

Some premise indicators

• since
• because
• for
• given that

​But sometimes an argument is presented without any of these premise or conclusion indicators, and you just have to think: “What is this person trying to convince me of?  What is their point?”  The thing they’re trying to convince you of is their conclusion.