Nor is an argument just the denial of what the other person says. Even if what your opponent says is wrong and you know it to be wrong, to resolve your dispute you have to produce arguments. And you haven't yet produced an argument against your opponent until you offer some reasons that show him to be wrong.
When you're arguing, you will usually take certain theses for granted (these are the premises of your argument) and attempt to show that if one accepts those premises, then one ought also to accept the argument's conclusion.
Here's a sample argument. The premises are in red.
Some common premise-flags are the words because, since, given that, and for. These words usually come right before a premise. Here are some examples:
Your car needs a major overhaul, for the carburetor is shot.Some common conclusion-flags are the words thus, therefore, hence, it follows that, so, and consequently. These words usually come right before a conclusion. Here are some examples:
Given that euthanasia is a common medical practice, the state legislatures ought to legalize it and set up some kind of regulations to prevent abuse.
Because euthanasia is murder, it is always morally wrong.
We must engage in affirmative action, because America is still a racist society.
Since abortion is a hotly contested issue in this country, nobody should force his opinion about it on anyone else.
You need either a new transmission, or a new carburetor, or an entirely new car; so you had better start saving your pennies.Authors do not always state all the premises of their arguments. Sometimes they just take certain premises for granted. It will take skill to identify these hidden or unspoken premises. We will discuss this more later.
Affirmative action violates the rights of white males to a fair shake; hence it is unjust.
It is always wrong to kill a human being, and a fetus is undoubtedly a human being. It follows that abortion is always wrong.
A woman's right to control what happens to her body always takes precedence over the rights of a fetus. Consequently, abortion is always morally permissible.
Euthanasia involves choosing to die rather than to struggle on. Thus, euthanasia is a form of giving up, and it is therefore cowardly and despicable.
Whether an argument convinces us depends wholly on whether we believe its premises, and whether its conclusion seems to us to follow from those premises. So when we're evaluating an argument, there are two questions to ask:
If we don't accept the premises of an argument, we don't have to accept its conclusion, no matter how clearly the conclusion follows from the premises. Also, if the argument's conclusion doesn't follow from its premises, then we don't have to accept its conclusion in that case, either, even if the premises are obviously true.
So bad arguments come in two kinds. Some are bad because their premises are false; others are bad because their conclusions do not follow from their premises. (Some arguments are bad in both ways.)
If we recognize that an argument is bad, then it loses its power to convince us. That doesn't mean that a bad argument gives us reason to reject its conclusion. The bad argument's conclusion might after all be true; it's just that the bad argument gives us no reason to believe that the conclusion is true.
Let's consider our sample argument again:
So this argument does not, by itself, establish that Shoeless Joe Jackson paid tuition to NYU.