The following is an excerpt from The Joy of Argument. If this passage gets you thinking about how you can more effectively use argument in day-to-day life, check out the complete book in paperback or e-book format here.
To realize the joy of argument and all the wonderful things it can bring, you need to think about and say things that matter. Don’t just say things because it feels good to say them. Say things because they are relevant and help prove your point.
Start by arguing relevant facts. And spend most of your time on the most relevant facts. A fact is relevant if it tends to prove your point; these are the facts you emphasize when you are proving a point. For example, let’s say you argue that there is an economic recession. Relevant facts would be decreased income levels, decreased gross domestic product (GDP), decreased consumer spending, and increased unemployment. These facts, if true, would tend to prove your point.
But before you declare victory, keep in mind that a fact is also relevant if it tends to disprove your point; these are the facts your opponent emphasizes when he tries to prove you wrong. Increased income levels, increased gross domestic product, increased consumer spending, and decreased unemployment, if true, would tend to disprove your point. These facts make up the “other side of the coin,” and you should be aware of them if they are true.
So it’s important to identify the relevant facts in an argument. But it’s not enough to simply argue relevant facts in an argument. To persuade, you need to argue the most relevant facts. Let’s say you and a friend are arguing about whether there is an economic recession. Your friend says, “I just came back from Dubai. The business-class lounge was packed. The plane was completely full. Where’s the recession? I don’t see any recession!” Is it relevant that the business lounge in Dubai International Airport is full? Sure, a busy airport is a sign of economic activity. But is this the most important fact as to whether there is a recession? Probably not. First, airports tend to attract people with money, so an airport is not always the best barometer of general economic conditions. Second, airlines have been running their planes fuller in recent years because of consolidations, partnerships, elimination of unprofitable routes, technology, and fuel costs. And many seats are taken by off-duty airline staff and passengers using frequent-flier miles. These factors don’t tend to indicate the end of a recession. So the most relevant facts in this argument are probably broader economic statistics–for example, income levels, unemployment, GDP, and consumer spending (a tiny fraction of which would be found in the business lounge).
The most common flaw in bad arguments is saying stuff that is not relevant. Most bad reasoning comes down to saying things that don’t prove, or even tend to prove, the point. Say things that matter, and especially the things that matter most, and you stand a much better chance of persuading.