6 things NOT to do if you want to win an argument

Twitter's reduced our ability to argue coherently or effectively but it's not entirely to blame. Here's how to use proper logic to prove everyone else wrong

09 September 2018 - 00:00
Why is it so hard to use logic to prove everyone else wrong?
Why is it so hard to use logic to prove everyone else wrong?
Image: 123RF/wavebreakmediamicro

Wife (shouting from the bedroom): "Come to bed, it's late!"

Husband (furiously banging on his keyboard): "I can't! Someone is WRONG on the internet!"

That's a cartoon currently doing the rounds from screen to screen. It speaks to anyone who has ever been involved in a cyber-debate, which - unless there is an undiscovered subspecies of humans with no opinions - is everyone with online access.

At the risk of teaching grandmothers to suck eggs (whatever that might actually mean), it seems necessary to define a few things here. A debate is a situation - for example, "the land debate" - in which people who disagree about something air their opposing views. A debate involves disagreement, but to call it an argument is not strictly correct.

The difference between a debate and an argument is a matter of some dispute. Many people use "argument" to refer to the disagreement itself rather than the points of view held by the opponents, but pedantically speaking an argument is a claim made on the basis of supporting evidence.

That's all very well as a theory but it seldom applies to real-life arguments. We can't hold the internet responsible for all the ills of society, tempting as that may be, but the granting of a public stage to every opinion-holder has vastly increased the noise of debate while proportionately decreasing the soundness of arguments.

Social media has reduced our ability to argue coherently or effectively but it's not entirely to blame. Ego and sloth also contribute

Social media has reduced our ability to argue coherently or effectively but it's not entirely to blame. Ego and sloth also contribute. Few take the time to verify facts or consider an issue from all sides, either because we're convinced of our own inviolable rightness or because it just feels like too much effort.

The land debate has turned into what might be called a bad debate because
no-one wanted to wait until evidence was gathered and solid arguments presented before jumping into the ring and throwing punches.

A good debate demands time and effort, both in the formulation of sound arguments as well as in the willingness to calmly evaluate and rationally engage with counter-arguments.

A common reaction to that particular argument is: "But I'm totally calm! It's the others who won't listen. They are completely irrational."

And right there is a logical fallacy, one of those potholes into which we fall while picking our way along the road to reason.

Aristotle (384-322BC) came up with a bunch of fallacies, which have been added to and expanded upon and refined by many thinkers over the past two millennia but (like humans) have changed surprisingly little in the defective logic they describe.

It is unlikely to happen on Twitter, but let's assume there is a place in the world for productive debate. Getting there requires better arguments and more logical responses to counter-arguments, both of which would benefit by trying to avoid at least the following six standard fallacies:


This is when you attack the character of the person rather than their argument. It is a firm favourite among online debaters because it provides an easy way to avoid grappling with the actual issue while at the same time venting some satisfactory spleen.

"Why would I take seriously anything said by a person who picks his nose?", "I can't argue with someone so stubborn", "You're saying that because you're a racist" and "You're an idiot" are all forms of the ad hominem fallacy, and they all block the way to progress.


If you pick on one aspect of a person's argument and exaggerate it out of proportion to the whole of what they're saying, or if you misrepresent their argument to make their motives sound suspect, you are committing the straw man fallacy.

An example can be found in this response to the land debate: "If President Ramaphosa is willing to consider changing the constitution to allow land to be expropriated without compensation, he clearly hates all white farmers."

It doesn't take a student of philosophy to point out the logical holes in that argument.


This fallacy occurs when you take what is relevant to a small group and apply it to a much larger group without considering whether your sample is representative enough to reach such universal conclusions or whether other causal factors might also be at play.

For instance: "Five children in my son's class have head lice. There are 30 kids in the class. This means that one out of every six children in SA has head lice."

Even the most illogical Twitter user would point out that an outbreak of lice at one school is unlikely to indicate a nationwide plague.

On a far more sensitive subject, there is a glaring hasty-generalisation fallacy in the argument claiming that the murder of white farmers in SA is proof of a planned racial genocide, but those who dare point this out open themselves up to the most vicious of straw man and ad hominem attacks.


Also known as the fallacy of irrelevant appeal to popular opinion, this is the type of fuzzy thinking that claims something must be true if everyone thinks it is true.

 For example: "All my friends listen to Justin Bieber, therefore Justin Bieber is the best singer in the world."

The masses can sometimes be wrong, as Copernicus said when placing the sun at the centre of the universe.


This is the fallacy committed when the proof of your argument relies on a decidedly unreliable source, or at least a source whose credentials as an authority in the field you're arguing about have not been established to the satisfaction of the person you're trying to convince.

For example: "My beautician says people who live in the informal settlement outside town are all fine in terms of their basic needs, so I'm not going to worry about them."

Rejecting this argument does not mean you doubt the intelligence of beauticians; it's a question of the beautician's authority to comment on this issue. If she has met every person who lives in the informal settlement and knows exactly how much shelter, warmth and food each of them has, she might be considered an authority whose opinion should be taken seriously when considering such matters. If not, the argument commits a gigantic fallacy.

(Note that the argument is not whether one should worry about those in need; the assumption seems to be that if people are not fine then that would be cause for concern. Relying on a completely unqualified opinion to salve one's conscience is a cop-out.)


The fallacy of appeal to ignorance is when a lack of evidence for one thing leads you to claim that another thing must be true, without interrogating other reasons for the possible invalidity of the other thing.

For example, "It can't be proved that climate change is due to fossil-fuel emissions, therefore we should carry on using coal", or "Science has not definitively shown that the Big Bang ever happened, therefore God exists".

There is a school of thought that claims the point of debate is not to win but to learn. There's not much evidence of this kind of thinking on Twitter

There might be logically sound arguments for using coal or believing in God, but these are not them.

There is a school of thought that claims the point of debate is not to win but to learn. There's not much evidence of this kind of thinking on Twitter - or anywhere else for that matter - but it's worth bearing in mind.

Whether you believe that arguments exist to help us listen and grow, or whether, as is far more common, you think the only reason to argue is to make others agree with you, it helps to have a sound argument in the first place. Recognising lapses in logic is a good place to start.